Help Pressing F1 anywhere in the application will bring up the help screen. ESC will exit the help screen. Note : Press TAB to highlight(dark blue background) the next help topic(the yellow text below). Then press enter to view it. Or just click on a desired topic with the mouse. INDEX OF TOPICS: Creating Loading Modifying Printing Plots Printing Fitted Viewing Plots OTHER TOPICS: CurveFits Menus Data reduction Importing Files About CurveFits File Create Use this option to begin entering data for a NEW data file. You will first be asked for the name of the data file you wish to create. If a file with that name exists, you will be then notified and asked if you wish to overwrite it or not. File Use this option to load a pre-existing Curvefits data file. File Use this option to either: a a) Save your newly created data file using File|New b) Save your modified Curvefits data file. File Load&Fit This is an 'express' option. It will load a pre-existing curve fits file, run it through the curve fitting process and then take you to the fit selection dialog. File Change Directory Use this to change the current directory of Curvefits File View Text Use this option to use the internal file viewer to examine text files. Useful for examining text data files that you want to import. Note that the viewer will only display the first 64K of the file. File Set Printer This option allows you to choose your printer (either Epson or Laserjet & compatibles) and select the port to print to (LPT1 - LPT9) File Dos Shell This option will shell you to the DOS command line. Data Add Pair This option allows you to add a data pair to the currently loaded data file. Data Delete Pair This option allows you to delete the highlighted data pair from the currently loaded data file. Data Modify Pair This option allows you to modify the values of the highlighted data pair Data Add Loop This allows the addition of multiple data points to data file. The program will loop through the data pair addition process until either the Cancel button is selected or the Esc key is pressed. Data Reduce This allows you to multiply all the data pairs in a data file by two constants. One for the X value and another for the Y value. This is good for reducing the magnitude of data files that have large values, which tend to overflow the exponential functions. Data Import Text You will be asked for the name of the data file you wish to convert, and a formating string for the text file data. For numbers you wish to use you will specify the code '%Le' in the format while numbers that are to be ignored will be specified with '%*Le'. The format string will tell the program what each line in your text file looks like, and therefore how it should be processed. U For example, if your text file looks like this : 1.01232 12.8373 2.98210 4.87371 You would use this format string : %Le %Le If there are more than two numbers per line, you can specify which numbers you want to use (realizing of course that CurveFits can only use TWO data points). ) For a text file that looks like this : 16.9872E+02 16020202020.2 -1928.34E-02 123.32323 1.32233 22332.2 If you wanted to use columns one and three use the following format string : %Le %*Le %Le or if your data appears like this : 1.4, 2.11 6.1, 12.32 use this format string : %Le, %Le compare this with the previous : 1.22982 , 12121 corresponding format string : %Le , %Le Any amount of consecutive spaces can be reduced to one space but any spacing between commas, numbers etc MUST be noted. You must also use an %Le or %*Le for EVERY number appearing on a line. One last more complex example: text file: time = 1, velocity = 3, acceleration = 6.82287 time = 2, velocity = 4, acceleration = 5.28701 appropriate format string is : time = %Le, velocity = %*Le, acceleration = %Le Also keep in mind that the format string IS case sensitive! Data Output Text This will convert the currently loaded data file to a text file. Fits Perform Fits This will perform the curve fits on the currently loaded data file. The length of this process depends on the size of the data files. On a PC with an 80386/20Mhz CPU plus an 80387 math coprocessor, a data file with 100,000 points will take about 17.5 minutes, 1000 points about 8 seconds. Fits Best Correlation This will display, in sorted order, the available fits by best correlation. Fits Best Std Err This will display, in sorted order, the available fits by standard error. Fits View Fits This will bring up the fit selection menu. Fits Desktop Colors This allows you to change the default colors of the desktop. Fits Graph Colors This allows you to change the default colors in graphics mode. Window This will move focus to the next window on the desktop. Window Previous This will move focus to the previously focused window on the desktop. Window Close This will close the currently focused window on the desktop. Exit Exit the program and return to DOS CurveFits 4.27 Main Menu Option: CF515 equivalent keystrokes: (1) CREATE DATA FILE Alt-F1 (2) LOAD/ERASE DATA FILE F2 ( erasing no longer supported ) (3) EDIT DATA FILE F2 (4) CURVE FIT MENU F4 Alt-V (5) EXIT PROGRAM Alt-X Best Window The 'Best' window (either Best Correlation or Best Standard Error) displays the list of available fits in sorted order. Pressing enter will display the plot of the hilighted fit. Clicking on a fit will display it also. Press enter for more Help. Data Window Press enter for more Help. M This is a display of all the data points in the currently loaded data file. 1 The data file can be modified from this window. Enter - Will allow you to change the values of the currently highlighted data pair. (Also can be accomplished by clicking on a pair with the mouse). Delete - Will delete the currently highlighted data pair. Insert - Allows addition of a data pair to the file. Fit Selection Box The Fit preceded by the 'R' has the best correlation coefficient while the fit preceded by the ' ' has the best standard error. Fits that are unavailable will be marked with 'N/A' (Not Available). This can happen for three reasons: (1) Data has values which would cause calculations to have undefined results (division by zero, logarithms of zero and below etc.) (2) Data has caused FPU registers to overflow/underflow during the calculation of equation coefficients. (3) Polynomial fit cannot be used on file with less than 4 data points. (Use quadratic or linear fit) CurveFits v5.15 Curvefits is protected under the copyright laws of the United States. The program is Copyright, 1995 by the author John P. Arkins All rights reserved. D Curvefits is a curve fitting program written in Borland Pascal 7.0 9 Borland Pascal is a Trademark of Borland International. F SHAREWARE NOTICE ----------------- CurveFits is not in the public domain, it is shareware. If you find this program useful, please register it by sending the $25 registration fee to the below address. Any comments or suggestions are also welcome. Thank you very much. m Registration : John P. Arkins 54 Pearl Street New Hyde Park, NY 11040-3814 Comments Only: Compuserve : 73633,3417 Internet : 73633.3417@compuserve.com Creating at data file In order to create a data file, press ALT-F1. You will then be asked for the name of the data file you wish to create. If you specify the name of an existing file you will asked whether you wish to overwrite it or not. The program will then loop through the data entry process. Enter an X value, press either tab OR enter, enter a Y value and then press enter again as the OK button is now hilighted and will be activated. If a blank or invalid data field is entered the pair will not appear in the data window. The data entry loop will continue until either ESC is pressed or the Cancel button is selected. Loading the data file To load an existing CurveFits data file press F2. Enter the name of the data file you wish to load. The file will now be loaded and a data window will appear on the desktop. From here you can either modify file or run the data through the curve-fitting process by pressing F4. Hard Copy Plots can be sent to the printer from the graph screen. What is currently displayed on the screen is what will be printed. Therefore you should zoom and move about, select the data marking options etc that you desire. Q To send the printout to the printer , press E while viewing the graph screen. If you desire a text file listing of the original data along with the fitted values for it, press P when the graph is displayed. This will create a text file with the name '*.prn' where * is a number, 1 or greater. If 1.prn exists a file 2.prn will be created, and so forth. This can then be printed from the DOS command line by typing a line like: C:\>copy 1.prn prn E For listing of graph screen options press F1 from the graph screen. Viewing data plots In order to view a plot of the currently loaded data file, you must perform the curve fitting calculations on the data by pressing F4 or by selecting Perform Fits from the menu bar. After this you can see the fits in either two ways : # 1) Press Alt-V and bring up the fit selection box. 2) Select 'Fits' from the top menu bar and then either best correlation or best standard error. This will list the fits in appropriate order. Then highlight the fit you wish to see and press enter. You can also click on it with the mouse. In order to Import Text files into the program, the companion program CONVERT.EXE must reside in the same directory as CF515.EXE. This computer has failed a simple division test known to be performed incorrectly by PC's powered by Intel Pentium chips. Since this program performs many floatinmg point calculations with the notorious FDIV instruction, the data produced may be suspect. File Clear Desktop Closes all files, windows etc. Returns program to it's initial state.