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TexaSoft's SCIENCE FAIR GRAPHS & NUMBERS (C)Copyright 1984-1994 Alan C. Elliott ALL RIGHTS RESERVED All rights reserved. Printed in the United States of America. No part of this book may be reproduced without prior permission. No patent liability is assumed with respect to the use of the information contained herein. While every precaution has been taken in the preparation of this publication, the publisher assumes no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information herein. Note:There may be important information in the file LATENEWS.DOC. To view this file enter the command (from DOS) TXVIEW LATENEWS.DOC. NOTE:To print an order form, choose the "ABOUT" menu option. You will be given the option to print an order form. Or, you can print the fil SFORDER.TXT from DOS using the command PRINT SFORDER.TXT. For additional information on this product, contact TexaSoft, P.O. Bo 1169, Cedar Hill, Texas 75104 (214) 291-2115, Fax: (214) 291-3400, Compuserve:70721,3145. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 1 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- CONTENTS ----------------------------------------------------------- PART I Hints for Organizing Your Science Fair Project.....3 PART II AN OVERVIEW OF SCIENCE FILE GRAPHS AND NUMBERS....8 Program Requirements and Installation.................8 Using the Menu System.................................8 Tutorial:Try This Example............................11 PART III USING SCIENCE FAIR GRAPHS AND NUMBERS...........14 How Data is Stored...................................14 Designing and Creating a Database....................14 Using a Predefined Database structure...........15 Defining Custom Fields in Your Database.........15 Limitations to the Database..........................16 Example Graphs.......................................16 Creating a Bar Chart............................16 Creating a Pie Chart............................17 Creating a Scatterplot/Regression Line..........17 Creating a Time Series/Line Plot................17 Descriptive Statistics Example.......................17 Creating a Database.............................19 Entering the data...............................20 Calculating Summary Statistics..................20 Viewing the results.............................23 Choosing Which Database Mode to Use..................23 Using the spreadsheet entry mode................23 Using the database entry mode...................24 Editing Database information.........................24 Correcting errors in the database...............25 Using Entry & Edit Screen Function Keys.........25 Editing, Deleting and Packing Data..............25 Modifying and Displaying the Database Structure.26 Listing the Database to the Screen...................27 Killing a Database...................................27 Exiting SF G&N.......................................27 Creating a New Field.................................27 Replacing the contents of a Field (Calculations).....28 Subsetting the Database..............................32 Setting and Using Missing Value Code.................33 Entering Data From other Files.......................34 Interpreting Error Codes.............................37 Problem Report.......................................38 Shareware Explained..................................39 -------------------------------------------------------------------- Become a Registered User, Print an Order Form 2 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- PART I: HINTS FOR ORGANIZING YOUR SCIENCE FAIR PROJECT A Science Fair project can be fun and exciting -- but only if you plan ahead, create a plan, and follow your plan. Here are some helpful hints to make your project more successful. This brief discussion is meant to give you ideas and directions. However, you may need to refer to your teacher's notes and recommended books for more details on the planning process. THINK THROUGH A TOPIC BEFORE YOU BEGIN Choosing a topic is sometimes the hardest part of doing a project. You want to choose something that is not too simple -- if it's too simple it probably won't get you a good grade. You also do not want your project to be too complex -- you'll work yourself to death, and then someone will think your parents did the whole project for you. The best way to pick a topic is to begin thinking of something that is of interest to you. Are you interested in the environment? sports? music? pets? food? magnets? motors? Make a list of things that your are interested in. From that list, think of problems or questions you have about these topics. Suppose you are interested in magnets. You might wonder what makes an electro-magnet stronger or weaker. Is it the gauge of wire used? Make a list of questions you have about the topic. Now -- this suggestion will often separate the A+ projects from the B projects -- ask someone who knows about the topic. Ask an engineer about magnets. Ask a vet about pets. Ask a chemist about ozone. Ask a biologist about germs. A simple phone call to someone you know or someone your parent knows can make a big difference in the outcome of your project. Also -- some communities have Science Fair stores that are full of ideas, projects and supplies -- plus the people working at these stores can often help you focus in on an interesting and fun project. You might also refer to these or other books that can help you develop a project: BLUE RIBBON SCIENCE FAIR PROJECTS, by Maxine Haren Iritz, Tab Books, 1991 THE COMPLETE HANDBOOK OF SCIENCE FAIR PROJECTS, by Julianne Blair Bochinski, Wiley Science Editions. 1990 SUCCESSFUL SCIENCE PROJECTS, by Sandra Markle, Lothrop, Lee & Shepard Books, 1992. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 3 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- ORGANIZE AND PLAN YOUR EXPERIMENT Once you have decided on a topic, focus in on ONE important and answerable question. Do not try to answer a series of questions - - concentrate on a single testable question. For example, suppose you are interested in magnets. Instead of looking at a number of different magnet ideas, concentrate on one test -- for example, how does the wire used in a magnet effect its strength? Once you have settled on a single question, develop a way to test the question. In the magnet case, you can purchase magnet wire from stores such as Radio Shack or a Science Fair Store. Then you could create three (or more) magnets. For example 1) an electromagnet using small gauge wire 2) an electromagnet using medium gauge wire 3) an electromagnet using large gauge wire Without doing any testing, you should have some idea -- an educated guess -- of how the experiment will come out. This is called your hypothesis. For example, your hypothesis might be: Hypothesis: I believe that the electromagnet using the large gauge wire will be the strongest, and the one using the small gauge wire will be the weakest. Now how are you going to test this hypothesis? You must now design your experiment. DESIGN YOUR EXPERIMENT Your experiment should be designed with the specific purpose of providing evidence for your hypothesis. It is amazing how many experiments are so badly planned that the results offer no real evidence to support the hypothesis. Think through the experiment, and its possible outcomes carefully before you begin. For example, ask your self questions like these: How will you measure your outcomes? Will you use a tape measure? a thermometer? a scale? counting? How will you make sure that there is no bias (some factor not being tested that favors one outcome over another)? In other words, you want to give each item you test the same fair chance. (You might look up the concept of random sampling to learn more about avoiding bias.) For example, in the magnet project you decide to measure the strength of the magnets by seeing how many small nails (for example 3 penny nails) they can pick up. You create three magnets using the same size piece of metal (for example, a 16 penny nail), and wrap the same amount of wire in -------------------------------------------------------------------- Become a Registered User, Print an Order Form 4 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- the same way around each of the three nail magnets (for example, two feet of wire). Using the same battery, you hook up the magnets one at a time, and see how many nails it can pick up from a pile of nails. Going Further (for 7th grade and above): The example above describes a simple experiment. Here is an idea to make the experiment more interesting: For a more detailed experiment, you would want to repeat the test several times. How will you make sure there is no bias? For example, the battery may be weaker on the second magnet, and weaker again on the third. Scientists hope to eliminate bias by repeating experiments several times under the exact same conditions. You should perform the magnet experiment three or four times. Repeating your test is a fundamental aspect of good science. Another aspect of repeating the experiment is to run the experiment in a different order each time. For example, the first time, you might try the magnets in this order: Small, Medium, Large. Then second time you would use a different order. For example, Medium, Large, Small. Use a different order each time you repeat the experiment. ANALYZE THE RESULTS Once you have observed how many nails the magnets will pick up, you an plot the results using the Science Fair program. For example, suppose in the simple experiment that you observed this data: MAGNET NAILS ---------- --------- SMALL 31 MEDIUM 38 LARGE 51 You could then create a bar chart showing the results. The tutorial included in the Science Fair program shows you how to create a bar chart using this data. Going Further (for 7th grade and above): If you repeated the experiment, so you have several observations for each magnet type, you might report and graph the average number of nails for each magnet type. Using the Science Fair Program, you could use the Descriptive Statistics option to calculate the mean (average) and a confidence interval for each insulation type. A confidence interval is a calculated range of numbers that, with a certain amount of confidence, contains the real mean of the information you are measuring. You could graph this as three lines, a middle thick line representing the average, and two thin lines -------------------------------------------------------------------- Become a Registered User, Print an Order Form 5 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- representing the high and low confidence limits for the three insulation types. This presentation takes into account the spread (variance) of the data. For example, suppose you observed the following data Small Magnet Medium Magnet Large Magnet 31 38 51 33 40 48 29 39 47 30 37 50 To use the program to calculate the mean and confidence interval for each magnet type, enter the data into a database like this: Fields in the database (call it MAGNET2, for example) Field name Type Width Decimal Places SMALL Numeric 3 0 MEDIUM Numeric 3 0 LARGE Numeric 3 0 Use the descriptive statistics to calculate the mean (average) and a confidence interval for each magnet type. The results should be: Magnet Mean Low Limit High Limit SMALL 30.75 28.02 33.47 MEDIUM 38.5 36.44 40.56 LARGE 44.0 46.09 51.91 You could then create a bar plot with the mean as a bar and the low and high limits as points. To draw this plot, create a database (call it MAGNET3, for example) using these fields: Field name Type Width Decimal Places MAGNET Character 7 - MEAN Numeric 5 2 LOWLIMIT Numeric 5 2 HILIMIT Numeric 5 2 Then, enter the data where the first record will have MAGNET = SMALL MEAN = 20.75 LOWLIMIT = 28.02 HILIMIT = 33.47 and so on. Choose a bar chart, and plot the MEAN, LOWLIMIT and HILIMIT fields, using the MAGNET field as the label field. The chart will initially appear as a bar chart with three bars per -------------------------------------------------------------------- Become a Registered User, Print an Order Form 6 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- item. Use the <Options> menu item (second screen) to change the plot types for LOWLIMIT and HILIMIT from B (bar) to P (Point), and replot. The resulting plot will be three bars representing the three magnet types, with a two points on each bar representing the confidence limit. Since the limits do not overlap for any of the bars, you can conclude that the strengths of the magnets are indeed different, and that the higher the gauge wire used in the magnet, the more nails the magnet is able to pick up (all other factors being held equal). This plot clearly shows the average number of nails picked up by each magnet, and contains information on the spread of the observations. This kind of plot lets you see if averages are far enough apart to be considered a significant difference or not. If the confidence interval of one group does not overlap the confidence of another group, it gives you evidence to say that the averages are significantly different. For more information about the concept of statistically significant differences, consult a book on statistical analysis. EXPERIMENT CONCLUSIONS You conclusions for this experiment, based on the numbers and graph can be that the strengths of the magnets are indeed different, and that the higher the gauge wire used in the magnet, the more nails the magnet is able to pick up. The version of the experiment using repeated tests gives the most evidence to make this conclusion. This simple example has shown you some of the ways you can use the Science Fair program to calculate statistics and create graphs. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 7 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- PART II AN OVERVIEW OF SCIENCE FAIR GRAPHS & NUMBERS ==================================================== SCIENCE FAIR GRAPHS & NUMBERS (SF G&N) is a program that allows you to create graphs and calculate statistics that are commonly used for science, business and social study projects. PROGRAM REQUIREMENTS AND INSTALLATION SF G&N is designed to run on IBM PC and 100% compatible computers including the IBM PS/2 computers. It requires PC-DOS or MS-DOS version 3.0 or higher. Your computer should contain at least 512K or more of free RAM memory. SCIENCE FAIR GRAPHS & NUMBERS graphics require an EGA or VGA compatible monitor. HP Laserjet and Epson compatible printers are supported. A mouse is optional. To install on a hard disk, place the SF G&N distribution disk in the A: (or B:) drive and make A: (or B:) the default drive by entering A: (or B:). Then, enter the command INSTALL and follow the instructions on the screen. USING THE MENU SYSTEM Once you installed and setup SF G&N, to begin the program, enter the the SF command from the DOS prompt, in the \SFG directory. The menu system is very similar to a standard windows-like menu system. The main menu contains five options, File, Edit, Analyze Helps and About. Using the right and left arrow keys on the cursor pad, you can move the menu selection to one of the other menu bar options. Pressing the right arrow key once, moves the menu bar option from File to Edit. The FILE pull-down menu vanishes and the Edit pull-down menu appears. Pressing the left arrow key moves the selection back to the File menu. Or, point to a menu option with the mouse and click. To select options from an extended menu (pulled-down), use the up and down arrow keys on the cursor pad to highlight the option you desire, then press the Enter key. Or, press the first letter of the option name. If you are using a mouse, point to the selection with the mouse pointer and click. Here is brief description of each menu: -------------------------------------------------------------------- Become a Registered User, Print an Order Form 8 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- DEFINITIONS: ------------ DATABASE - a file containing information (usually numbers) that you will use to create your graphs or calculate statistics. In SF G&N, a database file uses the industry standard dBase II and IV format. FIELD - in this document same as variable. A field or variable is the name given a set of numbers in a database, such as AGE GROUP - a field containing information that tells the program from which group a record belongs. For example, a group field could be SEX, and contain the information F and M. If the SEX grouping field in record contained a F, the data would be about a female. If the SEX grouping field contained an M, the data would be about a male. LABEL - a field containing information that will be used as labels on a plot. STATISTICS - calculated values that summarize a collection of numbers. For example, the arithmetic average (also called a mean) of numbers is a statistic. VARIABLE - see Field above. USING THE FILE MENU Before you can create a graph or calculate statistics, you must enter numbers into a database. The DATA menu contains: o NEW DATABASE - Allows you to create a new database. You must create a new database and enter data before doing any analysis or creating a graph. The program creates and reads dBase (.DBF) type file format databases. o OPEN A DATABASE - Allows you to open an existing database. A database must be opened so the program will know where the data is located. o SUBSET DATABASE - Creates a new database that is a subset of the current database. o COPY/BACKUP - Creates a copy of the database. Useful to create a duplicate copy in case the original copy is damaged. o LIST (DISPLAY) THE CONTENTS OF THE DATABASE - Displays the information in the database to the screen. o MODIFY OR DISPLAY DATABASE STRUCTURE - Allows you to view or -------------------------------------------------------------------- Become a Registered User, Print an Order Form 9 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- change characteristics about the database, including field widths and types. o KILL DATABASE - Delete a database file from your disk. o EXIT - End the program. USING THE EDIT MENU The edit menu contains options that allows you to enter new data into a database, edit data currently in a database, and other editing options: o EDIT RECORDS - Change data already in the database. o APPEND RECORDS - Add new records to the database. o MISSING VALUE CODES - Define missing value codes for your database. o PACK DATABASE - Permanently erase all records marked for delete. o ZIP DATABASE - Permanently erase all records in the database. USING THE ANALYZE MENU The Analyze menu allows you to choose which analysis module to run. Initially, SF&G contains two options, o GRAPHS - Display and print graphs. o STATISTICS - Calculate, display and print statistics. o CREATE PROJECT LABELS - Allows you to print large character labels to your printer. When you choose an ANALYZE option, the analysis menu will appear allowing you to choose an option. USING THE HELPS and ABOUT... MENUS The SF G&N Help system contains several helps options: o PROGRAM HELP - Displays general helps about how to use the program, including brief examples of how to create a database for each type of graph. o TUTOR - Begins the tutorial that walks you through the creation of a graph. o CHANGE SETUP OPTIONS - Change program options such as color, default entry mode, printer type and monitor type. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 10 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- o DEFAULT PATH SPECIFICATION - Change the default path where you store your data. o AUTOHELP/HINTS - Toggles the Autohelp feature on or off. o GO TO DOS - Temporarily exit program to the DOS prompt, then return with the EXIT command. The ABOUT... menu displays copyright information and allows you to print an order form. ------------------------- TUTORIAL:TRY THIS EXAMPLE ------------------------- This short tutorial will give you a feeling for how to use SCIENCE FAIR GRAPHS & NUMBERS. It is not intended to be thorough, but simply to lead you though creation of a common graph. It will assume you are using SF G&N on a hard disk. To begin SCIENCE FAIR GRAPHS & NUMBERS, you must first be in the \SFG directory on your hard disk. Use the CD (Change Directory) command from the DOS prompt to change to the \SFG directory by using the command: CD \SFG Once in the \SFG directory, begin SF G&N with the SF command: SF The FILE pull-down menu will appear. (If the Analyze menu appears, press the left arrow key twice to open the File menu.) This example will use data already stored in a dBase ".DBF" file named EXAMPLE currently on the SF G&N disk. Follow these steps: 1. Open the database named EXAMPLE by selecting the OPEN DATABASE option from the File menu, then choose EXAMPLE from the list of files. (If the EXAMPLE database does not appear on the list of databases, you may not have installed the program correctly.) Once the database is opened, a notice at the bottom of the screen tells you that the database named EXAMPLE is open, and it contains 50 records. 2. Choose the LIST DATABASE option from the menu. This will list the contents of EXAMPLE database to the screen. Press Enter several times to list the entire database to the screen. When the list is finished, you will return to the File pull-down menu. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 11 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- 3. Choose the Analyze pull-down menu. 4. From the ANALYZE menu, choose the GRAPHS option. SF G&N now switches to the Graphs (which may take a few seconds). Soon, you will see the Graphs module menu. 5. From the Graphs menu, choose the TIME SERIES PLOT option The program now displays a screen with the fields available for use by the graph. The field names appear in a pick box to the left of the screen, and an empty box appears at the right of the screen. 6. From the left screen (list of fields), choose which fields to plot in the time series plot. Choose the fields TIME1 and TIME2. HINT: To choose a field, point to it with the mouse cursor and click once, or use the up and down arrow keys to highlight the field name and press enter. When you choose a field, it will appear in the "FIELDS TO GRAPH" box. After you choose the two fields, choose FINISH CHOOSING VARIABLES. After a few seconds, a time series plot will appear containing two lines. The menu at the top of the page can be used to selection a number of options for the graph. The options include: o EXIT - exit the graph and return to the menu. o Options - choose options for the graph including title, axis names, footnote, and other options. o PRINT - print the graph to your printer. o CAP/PCX - capture the graph as a PCX file. o Get Color - choose colors to be used to display the graph. o < + > - Smartpoint (tm) pointer used to select a datapoint on the screen. Information about the point will be displayed. 7. On all graphic screens in SF G&N, a similar menu will appear at the top of the screen. If you want the menu to temporarily vanish, press the spacebar. Press the spacebar again for the menu to reappear. The menu is active even if it is not shown. HINT: To choose an option from the graph option menu, press the first letter of the option or point to the option with the mouse pointer and click. 8. If you are using a mouse, place the mouse pointer on a datapoint on the screen and click. Or, if you are not using a mouse, press the -------------------------------------------------------------------- Become a Registered User, Print an Order Form 12 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- + (plus) key, then use the cursor keys to position the + over a datepoint on the screen, and press Enter. Information about the datapoint you selected will be displayed on the screen. This feature is particularly helpful in identifying points that are interesting or "outliers." Press Enter to return to the plot 9. Press G or click on the < get color > option. The color menu will appear. From this menu you can select color options. Experiement with these choices to see how you can change the colors of the plot. Most plots contain the following "get color" menu: o Menu - returns to the main graph menu o Graph - changes graph colors o Screen - changes background screen colors o Labels - changes label colors o Default - return plot to original default colors o B&W - diaplys plot in black and white o Help - displays help system o + (plus sign) - activates Smartpoint Some get color menus also contain the option: o Tile - paints the plot using tiles rather than solid colors HINT: You can use a captured PCX file to import into other programs, such as WordPerfect or Paint. TIP: When you choose to print or capture the screen, the menu will vanish, so the menu will not appear on the printout or PCX graphic. 10. Choose Exit to return to the Graph menu. Choose Exit again to return to the main menu. NOTE: You can also go through an on-screen tutorial on how to create a chart by choosing the TUTORIAL option on the HELPS menu. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 13 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- PART III -- USING SCIENCE FAIR GRAPHS AND NUMBERS ================================================= The SF G&N FILE pull-down menu in the main SF G&N module is used to manage your data. From this menu you enter data, change data, create new data fields from existing ones, and perform other data maintenance tasks. Once your data is in the SF G&N database, you can access the data from any of the other SCIENCE FAIR GRAPHS & NUMBERS modules. HOW DATA IS STORED A SF G&N database uses the same file format as the dBase III and dBase IV programs. Therefore, data already stored in a dBase III or dBase IV file may be read directly into all the SF G&N programs. The only exception to this is that SF G&N does not read dBase MEMO fields. Therefore, if your data in dBase contains memo fields, you may have to create a subset of your database before using it in SCIENCE FAIR GRAPHS & NUMBERS. Data from other programs can also be used in SCIENCE FAIR GRAPHS & NUMBERS. Refer to the section called "Entering Data into the Database." The menu for the file options appears as the FILE option on the main SF G&N menu. The following information describes how to use the options in this menu to create, manipulate and modify a database. The Open Database option on the Data menu allows you to access information in a dBase file that you created in SCIENCE FAIR GRAPHS & NUMBERS, in dBase, or in any other program that creates .DBF files. Use this option to choose the database that you will be analyzing. When you choose the OPEN option on the FILE menu, a list of databases currently in the default directory will be displayed. If the database you want to use is not in the current (default) directory, you can temporarily change the default directory by pressing the F2 function key. Once a database is open, you will see its name at the bottom left of the screen, along with the number of records in the database. DESIGNING AND CREATING A DATABASE The New Database option on the FILE menu is used to create a new database. The structure, or layout, of a database must be described before you enter your data. You need to give some thought to how your database will "look" so it will be in the proper format to do the analysis you desire. SF G&N allows you to create a new database in two ways: 1. Choose from a predefined structure or 2. Create a customized database -------------------------------------------------------------------- Become a Registered User, Print an Order Form 14 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- USING A PREDEFINED DATABASE STRUCTURE You can choose to create a custom database structure or you can choose from a list of pre-defined databases that are designed for specific analyses. The list below contains examples of some of the pre-defined database descriptions. For example, if you need to enter data for an bar chart, you would choose the option called "SIMPLE BAR CHART". The proper database structure for this analysis will be created and then you can enter your data into the database. Some of the predefined database options are: Simple BAR CHART database: Label and Value PIE CHART: Label and Value BAR CHART, 2 Groups:Label, Two values BAR CHART, Up to 5 Groups:Label, Five values HISTOGRAM or Statistics or Stem & Leaf, 1 Value HISTOGRAM or Statistics or Stem & Leaf, 1 Value, 1 group X-Y CHART/SCATTERGRAM, 2 Values X-Y CHART/SCATTERGRAM with GROUP, 2 Values, 1 GROUP TIME SERIES PLOT, 1 VALUE HINT: If you choose a predefined database structure that contains too many fields, you can use the editor to delete (or add) fields to make the database fit your needs. Or, if you have too many fields, you can just enter a dummy value such as 0 in each record of the field you do not need to use. DEFINING CUSTOM FIELDS IN YOUR DATABASE If you choose to create a custom database, you must tell the program what fields you want to use. If possible, always use a predefined structure. However, there may be times when you need to create a customized structure. Follow these procedures to create a custom database structure. 1. When you first enter the definition mode, the blinking cursor will be in the FIELD NAME area. Enter a name, (must begin with a letter, can contain letters, numbers and "_" (underscore) and may be up to 10 characters long) and press the ENTER key. The name you choose will be displayed in all capital letters, and the cursor will move to the next area, TYPE. 2. In the TYPE area, you only need to enter the first character of the type (N, C, L or D), - Numeric, Character, Logical or Date, then press the ENTER key. WIDTH is the number of characters reserved for the entry. DECIMAL is the number of decimal places (only for numbers). Note that the number of decimal places must be at least one less than the width. For example, if a number has the format ###.##, the width is 6 (count the -------------------------------------------------------------------- Become a Registered User, Print an Order Form 15 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- decimal point), and the number of decimal places is 2. If DATE or LOGICAL is entered as type, the program will automatically assign a width of 8 or 1 respectively. Unless your database is big, you might make each field one more character wide that you actually need. This provides for unanticipated large numbers and facilitates data entry. 3. Once a complete field description is entered, a next blank field description will appear, ready for entry. Enter information for each field needed in the database as described in steps 1 and 2. 4. To end the creation process, type Ctrl-END (^END). HINT:As long as you have not ended the procedure, you may use the cursor keys to back up, and make any corrections. If you mess up, end the procedure with Esc and begin again. 5. When you press ^End, you will be in the database entry screen, where you can enter your data. LIMITATIONS TO THE DATABASE Maximum of 250 fields. Maximum width of a field name is 10 characters. Maximum width of a cell is 60 characters (15 for numbers). Dates are always 8 characters and logical fields are 1 character wide. Memo fields are not supported. EXAMPLE GRAPHS Following are some examples of the kinds of databases you would need to create for several kinds of graphs: CREATING A BAR CHART Create the database and enter the data (see Creating a Database). Your database should look something like this: - It should contain a Label field & a Value field (the value field contains the numbers to use for the plot.) For example: the MAGNET is the LABEL field and NAILS is the VALUE field. ----these are the fields----- RECORD MAGNET NAILS ------ ------ 1 SMALL 38 -+ 2 MEDIUM 46 |--- this is the data to plot 3 LARGE 59 -+ | +----------------- these are the labels for the plot -------------------------------------------------------------------- Become a Registered User, Print an Order Form 16 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- NOTE: This will create a BAR CHART with 3 bars labeled SMALL, MEDIUM & LARGE. You could also use this same data to create a pie chart NOTE: You can have more than one value field, & create a side-by-side bar chart or a stacked bar chart. This data can also be used for a line chart or an area chart. CREATING A PIE CHART Create the database and enter the data (see Creating a Database). Your database should look something like this: - It should contain a Label field - It should contain a Value field (contains the numbers to use for the plot) For example: the COLOR is the LABEL field and COUNT is the VALUE field. This data refers to hair color for 50 people in your class. ----these are the fields----- RECORD COLOR COUNT ------ ------ 1 BLONDE 9 -+ 2 BROWN 14 |--- this is the data to plot 3 BLACK 22 -+ 4 RED 5 | +------------------- these are the labels for the plot This will create a PIE CHART with 4 slices. You could also use the same database to create a bar chart. CREATING A SCATTERPLOT/REGRESSION LINE Create the database and enter the data (see Creating a Database). Your database should look something like this: - It should contain a GROUP field (if you have more than one group) - It should contain two or more value fields (contains the numbers to use for the plot) For example: the SEX is the GROUP field and Height and Weight fields are the VALUE fields. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 17 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- ----these are the fields----- RECORD SEX HEIGHT WEIGHT ------ ------ ------ 1 M 70 202 -+ 2 M 65 145 |<-- this is the data to 3 M 72 188 | plot : F 60 103 | 22 F 62 122 | 23 F 59 112 -+ ^ | +------------------- this is the group field This will create a SCATTERPLOT and REGRESSION LINE PLOT. CREATING A TIME SERIES/LINE PLOT Create the database and enter the data (see Creating a Database). Your database should look something like this: - It should contain one or more value fields (contains the numbers to use for the plot) and an optional label field. For example: Sales1 is a VALUE field for team1 and Sales2 for team2. Data should be in a time order. In this example, sales for a month. ----these are the fields----- RECORD DAY SALES1 SALES2 ---- ------ ------ 1 1 4 3 -+ 2 2 5 4 |<-- this is the data 3 3 6 4 | to plot : 4 5 | 30 22 5 5 | 31 23 6 5 -+ ^ | +------------------ these are the labels DESCRIPTIVE STATISTICS EXAMPLE This example shows you how to enter data and perform some simple statistics and graphs. The data that will be used is listed below. The GRADE variable is the grade received in the class, AGE is age, SEX is sex, WT is weight and SCORE is the score on a pre-test (maximum of 25 points). In database language, these variables are called fields. GRADE AGE SEX WT SCORE 1 A 18 M 165 22.3 2 B 19 M 145 22.8 -------------------------------------------------------------------- Become a Registered User, Print an Order Form 18 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- 3 B 17 F 122 22.8 4 C 18 M 196 18.5 5 B 17 M 188 19.5 6 B 18 F 140 23.5 7 C 19 F 121 22.6 8 B 20 F 112 21.0 9 C 19 F 122 20.9 10 A 18 M 176 22.5 11 B 18 M 165 23.3 12 A 19 M 135 21.8 13 A 18 F 121 24.8 14 C 19 M 186 16.5 15 B 17 M 148 18.5 16 A 18 F 140 24.5 17 B 16 F 101 23.6 18 A 21 F 111 20.0 19 B 17 F 124 21.9 20 B 18 M 176 21.5 Before performing any kind of analysis on this data, you must first enter it into a database The process is: 1. Create a database 2. Enter the data 3. Perform an analysis These processes will be explained in the next few sections. CREATING A DATABASE When you begin the program, the main menu appears. If you have not yet created the database, you must choose the NEW DATABASE option, which will lead you through the steps in creating a database. This section describes that procedure. Note: Once a database has been created, you can use the data in it again by choosing "Open a database to use" from the Data menu. When you choose Create a new database from the Data menu, you will then be prompted to enter the name of the database. You need to enter a name for the database that is a DOS compatible file name such as MYDATA. Once you have entered a filename for the database, you can choose from a list of pre-defined database structures, or create your own. In this example, you will create your own database structure. From the menu, choose the CREATE A CUSTOMIZED DATABASE option. For each field (each item of data) in the database, you must specify a fieldname, a type a width and optionally the number of decimal places. For the data in this example, you will use the following information: -------------------------------------------------------------------- Become a Registered User, Print an Order Form 19 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- Field name Type Width Dec GRADE C 2 AGE N 3 SEX C 2 WT N 4 SCORE N 5 1 The GRADE and SEX variables are of type "C" (Character) and the rest of the variables are numbers "N". Notice that the widths defined here are actually 1 character wider than actually needed. If you are not pressed for space in the database, this will make your listings easier to read. Only the SCORE variable requires a decimal value. Enter the information about the database structure into the database definition screen. ENTERING THE DATA When you choose to enter the data in a new database, an entry screen will appear listing the names of all of the fields and an area to enter the data. The program includes two types of data entry screen, database type and spreadsheet type. In the Setup routine, you chose one of these two entry options. The following discussion shows you how to enter data in either screen. TIP: You can toggle between spreadsheet entry mode and database entry mode by pressing the F8 (Switch) key. CALCULATING SUMMARY STATISTICS Once you have entered your data into the database, you are ready to perform one or more analyses. Exit the data entry mode by pressing the F7 - Exit key. You will return to the main menu. All of the analysis procedures are listed in the Analyze menu. With the main menu displayed, you can press the right or left arrow key to pull-down the Analyze menu. For the MYDATA database you have just created, you will calculate some summary statistics and display a graph. From the Analyze menu on the main menu screen, choose the Statistics option. A new menu will appear containing the options for the Statistics program module. The Statistics menu lists the statistics you can produce from information in the current database. For example, suppose you want to calculate summary statistics for all of the numeric variables in your database. To do this, select the option called Summary Statistics on a number of variables. A screen will appear prompting you to specify what fields to use in the calculations. A list of the variables in the database appears. Enter the field numbers for each variable you want included in the analysis, separating each variable number with a -------------------------------------------------------------------- Become a Registered User, Print an Order Form 20 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- comma. For example, choose AGE, WT, and SCORE. Once you select the variables to use, you are prompted to choose a grouping variable. Choose SEX as the grouping variable. Calculations will take place and the results will be shown on the viewer screen: Variable Name is TIME1 From database:EXAMPLE.dbf N = 476 Missing = 0 Mean = 21.01261 St. Dev (n-1) = 2.47418 St. Dev (n) = 2.47158 Median = 21.30000 S.E.M. = 0.11340 Minimum = 3.00000 Sum = 10002.00000 Maximum = 33.00000 Variance = 6.12157 -------------------------------------------------------------------- Percentiles: 0.0% = 3.00000 0.5% = 7.08000 2.5% = 15.80000 ------------------------------ 10.0% = 18.50000 95.0% C.I. about mean is: 25.0% = 19.50000 50.0% = 21.30000 ( 20.79033, 21.23488) 75.0% = 22.60000 ------------------------------ 90.0% = 23.50000 97.5% = 24.20000 99.5% = 31.23001 100.0% = 33.00000 Here are some definitions concerning the statistics reported: DEFINITIONS: ------------ C. I. - Confidence interval - This is a range that describes (with some confidence -- usually 95% confidence) where the actual mean of the data probably lies. That is, the true mean of the data shown above is somewhere between 20.79 and 21.23, with 95% confidence. MAXIMUM - The largest number. MEAN - A measure of central tendency. The arithmetic average. For example if you average the 3 grades 82,100 and 88 (82+100+88)/3 = 90 -- the average (or mean) is 90. MEDIAN - A measure of central tendency. The mean is a statistic such that 50% of all numbers in the sample are above the mean and 50% are below the mean. For example, in the number list 1,2,3,4,5 the median would be 3. MINIMUM - The smallest number. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 21 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- MISSING - Reports how many numbers in the database had a missing value code. N - How many numbers were used to calculate the statistics. PERCENTILES - Tells you what percent of numbers are lower than the percentile. For example, the 50th percentile is the median. S.E.M. - The Standard Error of the Mean measures the spread of the data around the mean value. ST. DEV. - Standard Deviation - measure of the spread of the data. It is calculated two ways, using n-1 as a divisor and using n as a divisor. Usually, most people use the n-1 version. SUM - The total of all the numbers added together VARIANCE - A measure of the spread of the data. A menu of options appears at the bottom of the descriptive statistics screen. These options are: o Exit - Exits back to menu o Graph - Displays a graph of the data o View/Print - Allows you to view the results in the viewer, and to print or save them to a file. See "Using the Viewer" below o CI - Allows you to choose the level for the confidence interval o Percent - Allows you to choose the percents that will be displayed on the screen o New Variable - Allows you to choose another variables from the database to examine If you choose the graph option, the graph menu will appear. It contains the following options: o Exit - Exit the screen o Mean CI off/on - Toggles a display of a normal curve on the histogram and a confidence interval on the box and whiskers plot. o Print - Print the graph to the printer o < + > or < - > - Display the histogram using smaller or larger classes o Dist off/on - Toggles a display of the data as a cumulative -------------------------------------------------------------------- Become a Registered User, Print an Order Form 22 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- distribution instead of as a histogram o Cap/PCS - capture the screen as a PCX file o B&W or Use Color - Toggle screen from color to Black and White mode. VIEWING THE RESULTS The viewer allows you to examine output from an analysis that could be too big to appear on one screen. When the viewer appears, you can move around the displayed results by pressing the arrow keys, PgUp, PgDn, Home and End. If you are using a mouse, you can use the scroll bars on the right side and bottom to position the output on the screen. The function key commands available in the viewer are described below. To activate one of these commands, press the function key or click the option on the button bar at the bottom of the screen: F1 - Display this help screen. F3 - Send setup code to printer (for condensed print, etc.) F5 - Goto a line in the output (Press F5, then enter a line number.) F7 - Exit the viewer. F8 - Define size of margin for output. F9 - Define a title to be used on output. F10 - Output the contents of the viewed file to a printer or file. When you choose this option, the default output is the port you specified in the program setup (i.e., LPT1: meaning line printer port 1). You can press Enter to accept this default, or type a file name to save the contents to a file. CHOOSING WHICH DATABASE MODE TO USE The program allows you to enter and edit data using two modes -- the spreadsheet mode and database mode. When you installed the program, you chose one of these modes as a default. When you are entering data, you can switch from one mode to the other by choosing the F8 option. The following sections describe each of the modes. Use the mode that is most intuitive for you. USING THE SPREADSHEET ENTRY MODE The spreadsheet screen looks similar to a spreadsheet. If you prefer to use the database entry mode, skip to the section titled "Using a database entry screen." The names of the database fields (Grade, Age, etc.) are listed at the top of the screen (columns) and the record numbers are listed down the left side of the screen (rows). Since you do not have any records entered into the database, the only row displayed is the -ADD- row, which indicates that you are adding a new record. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 23 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- To enter data into the database, begin typing the entry for the first field. For example, in the GRADE column you would type a grade such as an A, then press Enter. Your cursor moves to the next field (AGE). Type and age such as 18 and press Enter. Type a sex variable such as M and press Enter. Continue until you have entered all of the data for record 1. When you press Enter after entering the last variable in record 1, a new row appears to allow you to enter the second record of information, and your cursor moves to the first field of this record. Continue entering information in the spreadsheet until all records are entered. If you make a mistake on a record, you can use the right or left arrow keys to move your cursor and correct the mistake. If you discover that you have made an error in a previous record, you can use the Edit mode (described later) to correct this entry. To end the entry procedure, press the F7 (Exit) key. USING THE DATABASE ENTRY MODE This section describes how to enter data using the database entry mode. When you begin entering data into a new database, an entry screen for record 1 appears on the screen. The database entry screen displays each field name at the left of the screen followed by an entry field where you will enter the data for that field. For example, when the entry screen first appears, your cursor will be in the GRADE field. To enter the information for record 1, type the grade value for the first record, A (for example ) and press Enter. Your cursor will move to the next field. Type and age such as 18 and press Enter. Continue until you have entered all of the data for record 1. When you press Enter after entering information in the last field of record 1, a new entry screen appears for record 2 to allow you to enter the second record of information, and you cursor moves to the first field of this record. Continue entering information until all records are entered. If you make a mistake on a record, you can use the arrow keys to move your cursor and correct the mistake. If you discover that you have made an error in a previous record, you can use the Edit mode (described later) to correct this entry. EDITING DATABASE INFORMATION Once you enter data into your database, you may need to add new information, delete other information or change the database in some way. The following sections show you how to do modify and manage your database. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 24 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- CORRECTING ERRORS IN THE DATABASE Before returning to the main menu, you can correct errors by pressing the F2 key to toggle into Edit mode. The edit screen is similar to the screen used to enter data. Use the cursor keys to move to the field to edit, and change the value. Exit the edit screen with the F7 (Exit) command. If you end up with an extra record in your database, you can erase that record while in the Edit mode. To erase a record, place your cursor on the record and press F4 (Erase). The record will be permanently removed from the database. Exit the edit screen with the F7 (Exit) command. USING ENTRY AND EDIT SCREEN FUNCTION KEY COMMANDS When you are adding information to the database, there are several function key options that you can choose. These options are listed at the bottom of the entry screen. To choose an option, press the function key related to the option, or point to the option with the mouse and click. F1 - Displays the program Help menu. F2 - Toggles between edit mode and append mode. F3 - Deletes or Undeletes records. (Also use ^U) F4 - Erase or insert a record. F5 - Goto a record number. F6 - Undo - returns last record changed to it previous values. F7 - Exits entry mode and returns you to the main program menu. F8 - Switches between spreadsheet type entry and database entry mode. F9 - Insert or Delete a field in the database or Replace the contents of a field. F10 - Prints the contents of the current record to a printer or file. EDITING, DELETING AND PACKING DATA Once a database is created, you often need to correct information by editing records or getting rid of records. The following sections describe the process of changing the contents of a record by editing and a procedure for getting rid of records by deleting and packing. EDITING RECORDS If there is a need to change data already in a database, you may choose the Edit a record option from the EDIT menu. You will be asked to specify the record number you wish to edit. Editing is similar to entering data. Use the up and down arrow keys to move from field to field within a record. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 25 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- DELETE, ERASE or INSERT RECORDS If you want to erase an entire record within a database, use the edit procedure to display the record to erase. You can use one of two methods to erase a record: 1. Erase the record (Spreadsheet mode only) or (F4) 2. Delete and Pack (Delete is F3) To erase a record, display the record in Edit mode, using the spreadsheet entry mode. Highlight the record to erase, and press the function key F4. You can choose to erase more than one record at a time. Inserting records is similar to deleting records. In the spreadsheet mode, place your cursor where you want to insert (insert is above the current record). Press F4, then choose how many records to insert. If you want to temporarily "get rid" of a few records so that they will not be used in an analysis, mark them for delete using the F3 option Any analysis you perform will ignore deleted records. Then, if you want to restore them, unmark them again. This is a quick way to see how an analysis result would change if some selected records were not present in the analysis. PACKING THE DATABASE The records marked for delete are not actually deleted from the file at this point. However, they will be ignored in most analyses, and will continue to be displayed when you edit the database. You can undelete records from the Edit mode. If you want to permanently get rid of the records you have marked for delete, choose the Pack procedure from the File menu. This procedure erases all "deleted" records from the database. ERASING ALL RECORDS - ZAP A DATABASE The Zap option allows you to quickly erase all records from a database. To use this option, open a database, then choose Zap. MODIFYING AND DISPLAYING THE DATABASE STRUCTURE The Modify or Display database structure option on the DATA menu allows you to display the structure of your database, and allows you to change characteristics about the database structure. When you choose to display the structure, a list of all field names, their types, widths and decimals (if any) are listed. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 26 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- When you choose to modify a field, you age given a chance to the modify the characteristics of that field. Your options are: Change Name of Field Change Type of Field Change Width of Field Change Number of Decimal Places If you change the type of field, say from character to numeric, the program will attempt to convert the contents of the field to its new type. When you modify a database, you will be asked to enter the name of a new database. This means that the modified database will be in a new file, and your old original database will remain intact. If you no longer want the old database, you must delete it by choosing the Kill option from the File menu. LISTING THE DATABASE TO THE SCREEN The LIST option on the FILE menu allows you to look at the information in your database. The list produces an on-screen report that lists the data one record at a time. If your database contains too many fields to be displayed on the screen at one time, the list procedure will ask you at which field to begin the display. KILLING (DELETING) A DATABASE The Kill option allows you to delete a database and its related missing values files (if any.) When you choose this option, a list of databases will appear on the screen. Choose the database to delete, and the file(s) will be erased from your disk. EXIT SF G&N Use this option to end the program and return to DOS. CREATING A NEW FIELD The Edit mode allows you to create new blank fields of any field type, and to place information in those fields that is either a numeric or character expression. You may create a new field in a database within an edit screen by choosing the F9 (FIELD Insert) option. After creating a new field, you can then use the F9 (FIELD Replace) option to place a value in the new field. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 27 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- When you choose the Field option in the edit screen (F9), you will be prompted to enter information about the new field. Define a name for the new field Define the field type Define a width for the new field For numeric variables, Define the number of decimals, if any Define a missing value code. If none is selected, it is assumed to be 0 (zero). CAREFUL ATTENTION must be paid to the definition to assure that the calculated numbers will fit into the field width specifications. If the calculated number is too large to fit into the field, it will be given the missing value code. If an illegal calculation is attempted, such as a division by 0, the result will be missing. If a calculation includes a missing value, the result will be a missing values. TIP: To create a new field containing a new value that is a numeric transformation of other fields, first insert the new field using the F9 Field/Insert option, then use the F9 Field /Replace option to place the value in the new field. HINT: Be sure to use the backup command on the FILE menu to make a copy of your database before your change it. If you make changes to your database, and do not have a backup copy, you may make a mistake and lose important information. REPLACING CONTENTS OF A FIELD (Calculations) You can use the F9-Field Replace option in the Edit screen to replace the existing contents of a field, or place new information in a newly created blank field. The program provides a number of numeric and character functions to enable you to do this. For example, if you wanted to replace the contents of the field RATIO with the values WEIGHT/HEIGHT: 1) In the edit mode, highlight the field whose contents you want to replace. Press the F9 (Field) option, and choose Replace the contents of a field option from the Field menu. A dialog box will appear. 2) Specify which records to replace. The default it ALL, which means all records in the database. Or, enter a range such as 1-20, which would mean only perform the replacement in records number 1 through 20. Then, press Enter. 3) Specify what to place in the field. For example, enter the formula WEIGHT/HEIGHT in the Replace With entry field, where WEIGHT and HEIGHT are two other fields in the same database. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 28 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- 4) Specify any condition for replacing, if any. The default is NONE. For example, if you only want the replacement to be for records whose value of AGE is greater than 20, you would enter the expression AGE20 in the condition entry field. 5) Press F7 when you have finished entering the Replace information, and the replace will begin. When it is finished, you will return to the edit screen. The kinds of expressions you can use the Replace With and Condition fields are described below. SF G&N supports two kinds of expressions. One is strictly for mathematical expressions, called a math expression. The other expression type, called a database expression, allows the use of character, numeric, date and logical fields in the expression. Here are the criteria for when these are used: REPLACE WITH FIELD: Use either a math expression or a database expression. CONDITION FIELD: Use only a database expression. In the REPLACE WITH field, the default expression type is the database type. In order for an expression to be evaluated as a strictly math expression, you must place an equal sign "=" at the beginning of the expression. The major difference between the two expression types are in their capabilities. The database expression can handle most common calculations, including simple math, string evaluation, and date evaluation. The math expression can be used only for strictly numeric calculations using one or more of the functions listed in the table below, or that uses the exponentiation operator. For example, if you want to perform the calculation WEIGHT/HEIGHT, you can enter the expression as-is in the REPLACE WITH field. However, if you want to calculate the log of WEIGHT/HEIGHT, you must enter the expression as =LOG(WEIGHT/HEIGHT) since the LOG function is not supported as a database expression function. The equal sign signals to the program to use the math calculator. The information below outlines the capabilities of both expression types. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 29 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- Mathematical operators supported are Add +, Subtract -, Divide /, Multiply *, and Exponentiation ^ (Math calculator only). For Character fields, the database calculator supports the operation: Add + (appends one string to another). Following are a few examples of correct expressions: AGE/HEIGHT =SCORE^2 (= signals math calculation) LTRIM(FIRST)+' '+LAST Note: Literal strings included in expressions must be surrounded by single quotes. For example, 'Hello' is a literal string. Character field names are used without quotes. For example, NAME is a field name. A correct string expression using these two strings would be: 'Hello '+NAME TIP:Unless you use scientific functions in your calculations, you don't need to be concerned about which calculation type to use. Only if you use a numeric operation or function not supported by the database calculator will you need to place an equal (=) sign at the first of the expression. Database calculator functions supported The following functions may be used in expressions both in the Replace With and Condition fields. Database Calculator Functions ABS(NUM), ASC(STG), AT(STG1,STG2), CALENDAR(NUM), CAPS(STG), CHR(NUM), DATE(), DELETED(), IIF(LEXP,AEXP1,AEXP2), INT(NUM), JULIAN(DATE), LEFT(STG,NUM), LEN(STG), LOWER(STG), LTRIM(STG), MAX(NUM1,NUM2), MIN(NUM1,NUM2), RECNO(), REPLICATE(STG,NUM), RIGHT(STG,NUM), RTRIM(STG), SPACE(NUM), STR(NUM), STRING(NUM,NUM|STR), RIGHT(STG,NUM), STUFF(STG,NUM,NUM,STG2), SUBSTR(STG,NUM,[NUM]), TIME(), TRIM(STG), UPPER(STG), VAL(STG), Following a few example uses of these functions: ASC - Converts the first character of a string to its ASCII code. For example, the function ASC('A') would return the value 65, since 65 is the code for an uppercase A. AT - Returns the starting position of one character string within another character string. For example, the expression AT('Bill', 'Wild Bill') = 5 since the string 'Bill' begins five characters deep in the string 'Wild Bill'. CHR - Converts a number into its ASCII value. For example, CHR(65) is equal to the character string 'A'. DELETED - Returns a T if the current record is marked for delete, else it returns a F. Can be used to conditionally replace a value depending on if the record is deleted or not. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 30 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- INT - Rounds down to nearest integer. INT(3.2) would be returned as 3. LEFT and RIGHT - Returns the left or right portion of a string. For example, LEFT('Wild Bill',3) would return the string 'Wil' and RIGHT('Wild Bill',3) would return the string 'ill'. LOWER and UPPER - Returns lower or upper case string. For example, LOWER('Wild Bill') would return 'WILD BILL'. LTRIM, RTRIM and TRIM - Trims blanks from right, left or both ends of a string. For example, LTRIM('Wild Bill ') would return 'Wild Bill'. VAL - Returns the value of a string. For example VAL('24') is the number 24. Most of these functions are similar to or identical to functions used in the BASIC language or in dBASE or other database programs. For more examples, you might refer to documentation on these programs. MATH EXPRESSIONS The following functions are supported only in the Replace With entry field, and only for numeric field types. You MUST precede expressions using these functions with an = sign. An example of the RECODE function, which appears on the following table is: =RECODE(SCORE,1,AGE,10,15) The five arguments in the RECODE function are: No. Example Meaning 1 SCORE Field to use in compare 2 1 Value to assign if comparison is true 3 AGE Value to assign if comparison is false 4 10 Low range of field to compare 5 15 High range of fields to compare Thus, this example means that the value of the RECODE is 1 if SCORE is between 10 and 15, else the value is the current value of the AGE field for that record. Math Calculator Functions ABS(NUM), ASIN(NUM), ATAN(NUM), ATAN2(y,x), CSC(NUM), COS(NUM), COT(NUM), EXP(NUM), INT(NUM), LN(NUM), LOG(NUM), MAX(1,T2,3) MIN(1,T2,T3), MOD(NUM1,NUM2), PI, RAND, RECNO, RECODE(NUM1,NUM2,NUM3,NUM4,NUM5,NUM6), ROUND(NUM,DEC), SEC(NUM), -------------------------------------------------------------------- Become a Registered User, Print an Order Form 31 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- SIN(NUM), SQRT(NUM), SUM(NUM1,NUM2...), TAN(NUM), SUBSETTING THE DATABASE The Subset database option on the DATA menu allows you to create a new database from an old database. The new database can be a subset of the old one, using a conditional criteria for outputting information from the old database to the new one. For example, suppose you have a database with a field GROUP with values 1, 2, 3, 4 and 5. You want to create a database that does NOT include Group 5. After choosing Subset database from the DATA menu, you are asked for the name of the new database. For example, your new database might be named NO5.DBF. You are asked for the field name to be used in the selection criteria. In this case, you would choose the field named GROUP. Next you must enter the selection relationship. It will be described as a numerical expression. The conditional operators you may use are: = > < >= <= <> = and the logical operators .NOT., .AND., and .OR.. It is important that a dot (.) appear before and after each logical operator. For example, you might enter a condition such as AGE <10 .OR. SEX='M' When you choose the Subset option from the FILE menu, a Subset dialog box appears on the screen. There are two items you must enter in the Subset dialog box. First is a name for the new database. This must not be the same name as the current database. Then, you must enter the subset criteria. Example of subsetting criteria are: GROUP = 4 GROUP> STATUS GROUP < WEIGHT*HEIGHT TIME1 = TIME2*1.96 SEX = 'F' TIME1 <=20 .AND. SEX = 'M' When creating these expressions, you can use the same functions as was previously described in the table "Functions Supported for Character, Date and Value Expressions." -------------------------------------------------------------------- Become a Registered User, Print an Order Form 32 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- SETTING AND USING MISSING VALUES CODES Sometimes in the collection of data there are values that are lost or cannot be gathered. These are called "missing values". When such values occur, it is important for the program to know that the values are missing so that statistical calculations may take this into account. Missing values are usually designated as an impossible value. For example, the missing values designated for the variable AGE may be -9, since it is impossible for the variable AGE to have the value -9. When the program is asked to calculate the mean of age, for example, it will ignore those records where AGE is -9 in that calculation if -9 has been specified as the missing value code. In most SCIENCE FAIR GRAPHS & NUMBERS procedures, there is a casewise deletion of the record from calculation whenever a missing value is encountered. Once you designate a missing value code for a variable, it is up to you to make sure that this code gets placed into your database in the proper records and fields. For example, if you have designated -9 as the missing value code for AGE, you must make sure that in your database a -9 appears in the field AGE if that data is missing or unknown. A standard dBASE III file does not have a way to designate missing values, but SF G&N allows a way for you to designate these values in this program. The Indicate missing value codes option on the FILE menu is used to set up these values. When this option is selected, the program will display an entry screen that is similar to a data entry screen. You may enter one missing value for each field name. The missing value must obey the definition of the field in terms of length and type. Once missing values are entered, they are stored on disk in a file named filename.MV, where "filename" is the name of the designated database. If a new variable is created using the transformation procedure, its missing value is appended to the missing value file. You may change or correct the missing values for a database at any time by calling up this option. If missing values are already designated for the database, they will be displayed on the entry screen, and you may edit them or accept them as they are. IMPORTANT NOTE: If missing values are NOT used, and there is a blank numeric variable in a calculation, it will be treated like the value 0 (zero), so it is important to use missing values if your data contains such entries. Otherwise, the statistical calculations will be in error!! -------------------------------------------------------------------- Become a Registered User, Print an Order Form 33 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- ENTERING DATA FROM OTHER FILE FORMATS SF G&N was designed to read dBASE files and input ASCII files because these are among the most commonly used types of files to store data. If your data is already in a dBASE type file, you can read it directly into SF G&N. (You may need to delete any memo files in the database, if you have any). If your data is in another type of file, you may still be in luck. The next few sections discuss how to use data that is stored in other types of files, or to append new information from another dBASE file. ENTERING DATA FROM AN ASCII FILE When you choose to enter data from an ASCII file, you will be asked the name of the raw data file. (i.e., \MYDIR\MYDATA.DAT). The data from the ASCII file will be entered into the database, and a count of the records as they are entered will be displayed. If there are already records in the file, the new data from the ASCII file will be appended (added) as new records to the database. It is a good idea to go to the List procedure to look at the data to verify that it has been entered correctly. If the data does not match the fields, refigure the widths of each field to make sure it matches the columns of data in the disk file, and try again. SF G&N can read data from standard ASCII text files. These kinds of files are usually supported by most word processing programs (such as WordPerfect DOS Text Mode) as well as most text editors such as EDLIN or the DOS EDIT program. Data must be in the form of column data, like this... A 22 3.3 WF A 33 4.2 BF B 27 3.3 WM : ETC Notice that each column of data is in fixed fields. It does not matter that there is no space between the last two fields (Race and Sex) since the program will pick off the information from the column and does not require that there be spaces between the columns. Use the instructions below to prepare the SF G&N (dBASE) database structure to be used to read in ASCII data. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 34 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- The steps to enter ASCII data into SF G&N are: STEP 1. Use the NEW DATABASE option to create a database structure to match the columns in the ASCII file. The field widths MUST match the width of the columns of data on file. If there are spaces between columns of data, make widths wide enough to account for those spaces. The following data is from the file EX.DAT on disk: A 12 22.3 25.3 28.2 30.6 5 A 11 22.8 27.5 33.3 35.8 5 B 12 22.8 30.0 32.8 31.0 4 A 12 18.5 26.0 29.0 27.9 5 B 9 19.5 25.0 25.3 26.6 5 : etc : B 12 22.4 27.2 31.8 35.6 4 Try your hand at doing this example by creating a database named EX with the following structure: FIELD NAME TYPE WIDTH DECIMALS ----------- ------ ------- -------- GROUP C 2 AGE N 4 0 TIME1 N 5 1 TIME2 N 5 1 TIME3 N 5 1 TIME4 N 5 1 STATUS N 2 Notice that even though the first column has data 1 column wide, this structure uses a width of 2 for GROUP. Even though the age only uses 2 columns, the structure calls for AGE to have a width of 4. These widths are enter this way to take care of the blank spaces between the columns. If GROUP had been set up with only 1 column and AGE with only 2 columns, the ASCII data would not be read into the database correctly. Create the database called EX with the specifications listed above, then go to the next step. STEP 3: To verify that the data was read properly, use List option on the FILE menu to examine the resulting database. APPENDING DATA FROM ANOTHER dBase (.DBF) FILE If you have data in one database, and want to append information from another database, follow these steps: 1. Open the database (first database) where you want to append other data. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 35 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- 2. From the EDIT pull-down menu choose Append Records and From a DBF file option. 3. Specify the database that contains the records to be appended (second database). The records will be added to the end of the first database. Only records in the second database that match the same field names as the first database will be added to the first database. If the field widths or types do not match, the added records may not be correct. Be sure that the field names, types and widths match before appending records using this method. Also, list the records after appending to make sure they were added correctly. USING DATA FROM OTHER PROGRAMS Many other programs create .DBF or ASCII files. If you want to transfer data from a program such as Excel or Lotus 1-2-3, look up dBASE or DBF in the program's index or help file to see how to create a DBF type file. Once you save the data in a DBF file, it can be read into the SCIENCE FAIR program. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 36 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- APPENDIX INTERPRETING ERROR CODES If the program encounters a problem it does not know how to resolve, it will usually display an error message. This message will contain an error code and a reference code. Many times, you can correct this error situation by understanding what caused it. For example, if you were to get an error number 27, you would know that it was caused by your printer sending an "Out of Paper" message to the program. If you are unable to resolve the problem, write down the steps taken before the error occurred, and send it to TexaSoft on the Problem Report Form. We will try to resolve the problem as quickly as possible. Error Codes: Error Number 5 = Illegal function call Error Number 6 = Overflow Error Number 7 = Out of Memory Error Number 9 = Subscript out of range Error Number 11 = Division by zero Error Number 14 = Out of String Space Error Number 24 = Device Timeout - Check your printer or disk drive Error Number 25 = Device fault - Check your printer or disk drive Error Number 27 = Out of Paper - Check your printer Error Number 50 = FIELD overflow Error Number 51 = Internal Error Error Number 52 = Bad filename or number Error Number 53 = File not found Error Number 54 = Bad file mode Error Number 55 = File already open Error Number 57 = Device I/O error - Check your printer or disk drive Error Number 58 = File already exists Error Number 61 = Disk full - Erase files from your disk Error Number 62 = Input past end of file Error Number 63 = Bad record number Error Number 64 = Bad filename Error Number 67 = Too many files Error Number 68 = Device unavailable Error Number 70 = Permission denied Error Number 71 = Disk not ready - Disk drive door may be open Error Number 72 = Disk media error - You might have a bad diskette Error Number 74 = Rename across disks Error Number 75 = Path/File access error - Check default path name Error Number 76 = Path not found - Check default path name Error Number 81 = Invalid filename - Check default path name -------------------------------------------------------------------- Become a Registered User, Print an Order Form 37 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- Problem Report form: SF G&N Please explain in detail the problem that occurred. If possible, send a print out of the results or Print Screen. SF GRAPHS & NUMBERS version you are using:________________________ What were you doing when problem occurred:________________________ Your computer: Brand/Model____________________________RAM: _______ Printer type: (circle) Laser or Dot Matrix? Brand_________________ Monitor Type: (circle) EGA VGA Other:__________________________ Version of DOS you are using:__________________Disk Doubled? Y N Memory resident programs you use:_________________________________ On a Network? Y N If so, What kind/version________________________ Problem Description: Mail to:TexaSoft, P.O. Box 1169, Cedar Hill, Texas 75104. Or fax to 214-291-3400, or send E-Mail to Compuserve 70721,3145. -------------------------------------------------------------------- Become a Registered User, Print an Order Form 38 SCIENCE FAIR GRAPHS & NUMBERS MANUAL Ver 1 -------------------------------------------------------------------- S H A R E W A R E _________________ TRY IT BEFORE YOU BUY IT The purpose of shareware products is to allow you to try software products before you buy them. SF G&N is not a public domain program. Persons who use SF G&N on a regular basis should purchase a copy. You receive several benefits from becoming an official registered user: 1. You help to keep the product growing to meet your needs. 2. You receive the very latest disk version, and manual. 3. You receive periodic newsletters announcing new releases, and pointing out important information on any bugs and fixes. 4. You are able to purchase update to new versions for a minimal cost. Print the file on disk named SFORDER.TXT to register. Thanks. ┌─────────┐ ┌─────┴───┐ │ (tm) ──│ │o │────────────────── │ ┌─────┴╨──┐ │ Association of │ │ │─┘ Shareware └───│ o │ Professionals ──────│ ║ │──────────────────── └────╨────┘ MEMBER This program is produced by a member of the Association of Shareware Professionals (ASP). ASP wants to make sure that the shareware principle works for you. If you are unable to resolve a shareware- related problem with an ASP member by contacting the member directly, ASP may be able to help. The ASP Ombudsman can help you resolve a dispute or problem with an ASP member, but does not provide technical support for members' products. Please write to the ASP Ombudsman at 545 Grover Road, Muskegon, MI 49442 or send a CompuServe message via CompuServe Mail to ASP Ombudsman 70007,3536. 39