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G O A L S E E K E R
U S E R S' M A N U A L
Copyright 1987 Brown Bag Software
2155 South Bascom Ave
Suite 114
Campbell Ca 95008
U. S. A.
Tel: (408)559 4545
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
GETTING STARTED WITH GOALSEEKER
DISCRIPTION
GoalSeeker is used in conjunction with your spreadsheet (Lotus
1-2-3, etc.) to automatically find solutions with a "reverse" or
"backward" search method, also known as "goal seeking". Goal
seeking is the ability to achieve certain targeted values in a
spreadsheet by varying the associated data.
HARDWARE/SOFTWARE REQUIREMENTS
GoalSeeker requires an IBM PC, XT, AT or 100% compatible using DOS
2.0 or above. GoalSeeker requires approximately 40k of memory
overhead.
GoalSeeker must be run in 80 column mode with either a monochrome
or color graphics monitor in conjunction with your spreadsheet
software.
Although not required, GoalSeeker will utilize an 8087 or 80287
math co-processor chip if installed.
INSTALLING GOALSEEKER
Since the GoalSeeker archive contains four different versions of
the program, it is important that you select the correct one for
your spreadsheet program.
GoalSeeker supports SuperCalc4, Multiplan and VP Planner, as well
as Lotus 1-2-3. Copy the correct version of GoalSeeker onto your
spreadsheet system disk, or into the spreadsheet subdirectory of
your hard disk.
IF YOU USE A FLOPPY DISK SYSTEM
Insert the GoalSeeker disk in drive A:.
Insert your spreadsheet work disk in drive B:.
At an "A:>" prompt type:
COPY A:GS-#.COM B:GS.COM
Where # = 123 if you use Lotus 1-2-3.
SC4 if you use SuperCalc4.
MP if you use Multiplan.
VP if you use VP Planner.
IF YOU USE A HARD DISK SYSTEM
Insert the GoalSeeker disk in drive A:.
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Change into your spreadsheet sub-directory on your hard disk.
At a "C:>" prompt type:
COPY A:GS-#.COM GS.COM
Where # = 123 if you use Lotus 1-2-3.
SC4 if you use SuperCalc4.
MP if you use Multiplan.
VP if you use VP Planner.
TO START GOALSEEKER
To start GoalSeeker, change to the disk drive and sub-directory
where your spreadsheet is stored. If GoalSeeker has been properly
installed (as per instructions above), you can type "GS" at the
DOS prompt and then press the <Enter> key to run the program.
This will load GoalSeeker into the memory of your computer. You
can activate GoalSeeker while you are in your spreadsheet with the
push of a key. You must be within your spreadsheet to use the
GoalSeeker system.
NOTE:
If you use ANY other memory resident software such as
HomeBase you should load GoalSeeker FIRST.
Once GoalSeeker is loaded, start your spreadsheet as normal. When
the spreadsheet is displayed on the screen, you may activate
GoalSeeker by pressing the <ALT><SPACE> key combination. To do
this, hold down the key marked "Alt" with your left hand and press
the space bar with you right.
The GoalSeeker menu will appear on the top line of the screen
(over the top of your spreadsheet). The menu looks like this:
Help Goal Seek Parameters Multi-goal Review Quit
You may use the arrow keys to move to the desired option and press
the return key or simply enter the first letter of the option you
wish.
SET THE GOAL VALUE FIRST
Move the spreadsheet cursor to the desired GOAL cell. This cell
must be a "formula (calculated) cell". Press the <ALT><SPACE> key
combination, then press the "G" key for "Goal".
A rectangular box will be displayed over the original position of
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
the spreadsheet cursor. Type in the desired goal and press
<Enter>. Press the <Esc> key to cancel.
Example:
If cell B3 has a formula of "+A1*2", set a goal on this cell
of 128.00.
A B C D
1 12.00
2 GOAL
3 128.00
4
5
NEXT MOVE CURSOR TO SOLUTION CELL
Move the spreadsheet cursor to the cell you wish to vary to
achieve your desired goal. In our example above, move to cell A1.
This cell must be an "input (data) cell". Press the <ALT><SPACE>
key combination, and then the "S" key for "Seek".
This will begin the goal seeking operation. You will notice the
spreadsheet screen flashing as GoalSeeker begins its calculations.
Calculations will continue until the solution is found or the
maximum number of iterations is reached.
Example: (where B3 is +A1*2)
A B C D
1 64.00
2
3 128.00
4
5
When the solution is found, usually after 3 tries (iterations),
the message "SOLUTION FOUND" will be displayed at the top of the
screen.
Press the "R" key to "Restore" the original value or any other key
to continue. When the "R" key is pressed, the starting value in
the solution cell is replaced.
A SIMPLE DEMO
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
There is a demo worksheet named "DEMO" on your GoalSeeker
diskette.
After you have typed "GS" and pressed the <Enter> key at the DOS
prompt, load the worksheet DEMO into your spreadsheet. Follow the
steps outlined on your screen to see how easy GoalSeeker is to
use.
In this demo the following information is true:
"Sales" and "Expenses" are input numbers.
"Profit" is calculated as "Sales" minus "Expenses".
"TOTAL" is the sum of "Jan", "Feb", and "Mar".
"TOTAL Profit" is at cell G20 and we set the goal to $7,000.
We want to find what "Sales" are required in "Feb" (cell E17)
to reach our goal of $7,000 Profit for the 1st quarter.
GoalSeeker MENU
When you are in your spreadsheet and press the <ALT><SPACE> key
combination, a "1-2-3 like" menu will appear on the second line of
your screen such as the one below.
Help Goal Seek Parameters Multi-goal Review Quit
In the previous example, the word "Help" is highlighted. You may
use the right or left arrow keys on the numeric keypad to move to
the correct option, or you may enter the first letter of the
option desired (i.e., Pressing the "R" key will display the
"Review" window).
If you press the <Enter> key, the option currently highlighted
will be activated.
Under the menu is displayed one line explanation of the currently
highlighted option. When you change the highlighted option, the
one line explanation will change accordingly.
Pressing the <Esc> key will cancel the menu and return you to the
spreadsheet.
HELP OPTION
Help can be obtained from the GoalSeeker menu by pressing the "H"
key or positioning the cursor on the "Help" option and pressing
the return key. A help screen will be displayed.
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
GOAL OPTION
Two terms are defined here:
GOAL CELL is the cell where we want our target number.
GOAL VALUE is the desired goal.
The GOAL cell must contain a formula, because we will modify
another cell to get the calculated value of this cell to equal the
goal value you desire.
When you press the "G" key on the GoalSeeker menu, the following
message will be displayed at the top of your screen:
Enter the desired goal in the cell below & press return,
(Esc=cancel).
The current goal (xx) = yy.yy
Where xx is the goal cell and yy is the goal value.
A rectangular box with a blinking cursor will be displayed over
the GOAL cell (where the spreadsheet cursor was). The user may
enter the desired goal followed by pressing the <Enter> key or
press the <Esc> key to return to the GoalSeeker menu.
To see the original value in the cell, press the <Esc> key.
IMPORTANT
The GOAL cell will remain in the same location until you enter
another location. The GOAL cell value will not change even if you
insert or delete rows/columns, even if you change worksheets, or
even if you quit your spreadsheet and restart it later.
Example:
If you enter a goal value in cell C23, quit out of your
spreadsheet, restart your spreadsheet and load a different
worksheet, the goal cell is still defined as cell C23 with
the same goal value.
GOAL VALUES
The goal value must fit the following rules:
Be a numeric value.
Begin with one of the characters: 0 1 2 3 4 5 6 7 8 9 . -
Must not be entered with commas, dollar signs, or percent
signs.
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
Can contain up to 15 characters.
Must be between -1.e99 and 1.e99, although GoalSeeker stores
numbers ranging from -1.e308 to 1.e308.
Can only have one decimal point.
Can be entered in scientific format. For example,
"1.123E-12" or " .344-e44" would be acceptable, where the "E"
can be in upper or lower case.
You can use the following special keys:
You must press the <Enter> key when you have completed the
number.
You can press the key combination <Ctrl><H>, a backspace key,
or the left arrow key on the keypad to correct typing
mistakes.
The <Esc> key will cancel the number and return you to the
GoalSeeker menu. No goal value will be entered.
LARGE NUMBERS
The rectangular box is the same size as the size of the
spreadsheet column width; however, if you wish to enter a number
larger than the width of the box, continue to type the goal value
up to 15 digits.
GoalSeeker will allow you type past the edge of the box.
SCIENTIFIC FORMAT
A number may be entered with a power of 10 scaling factor. The
number may be up to plus or minus 10 to the 99th power. The
following chart describes the scientific notation standard.
upper or lower case E
1 or 2 digit number
xxxxxxE nn
either a plus or minus sign
any number, positive or negative
An example of scientific notation would be "1.234E-74".
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
SEEK OPTION
The Seek option is used to start the goal seeking process. You
should set the goal value first. For more information on setting
that value, see "Goal Option".
Move the spreadsheet cursor to the SOLUTION cell (the cell we are
going to vary) and press the "S" key (for "Seek") to begin
"goal seeking". You will see the screen begin to flash as
GoalSeeker tries new values in this SOLUTION cell.
SOLUTION FOUND
Once the solution is found, the correct value will be displayed in
a box in the SOLUTION cell, and the following message will be
printed on the top line of the screen:
SOLUTION FOUND
Press the R key to Restore the original value - any key to
continue
G H I J
23
24 SOLUTION 1.23 3.23 2.37
25 44.84 55.55 63.44 77.21
26
27
In the previous example, if you press any key except "R", the
solution will be accepted.
When the "R" key is pressed, the starting value (the value before
GoalSeeker began processing) is placed back into your spreadsheet.
If the recalculation mode is "Automatic", then the spreadsheet
will be returned to its original condition. If the recalculation
mode is "Manual", the starting value will be replaced, but a
recalculation will not be performed.
SOLUTION NOT FOUND
If the solution has not be found, the following message will be
displayed at the top of your screen:
Maximum number of iterations reached
Press the R key to Restore the original value - any key to
continue
GoalSeeker will choose the solution which came closest to the
desired goal as a final answer. Press any key to accept this
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
"best" answer or press the "R" key to "Restore" the starting value
in the SOLUTION cell.
If the solution was not found, you might try the goal seek again
with this new starting value. Usually, the closer the solution
value is to the actual value, the more quickly GoalSeeker will be
able to find the correct answer.
You may wish to look at the Review Option to determine how close
GoalSeeker came to the actual goal.
See the SPECIAL SITUATIONS section for more information on the
"solution not found" message.
PARAMETERS OPTION
Parameters are used to set limits on the goal seeking process.
There are 7 parameters which are used in GoalSeeker. When you
press the "P" key on the GoalSeeker menu, the "Parameters" window
will appear over the top of your spreadsheet.
To change one of the parameters, enter a number from 1 to 7. When
a number is entered, you may type in the parameter number,
followed by the <Enter> key. The <Esc> key will cancel the
current option and/or the parameters menu.
Option 7 toggles between "YES" to "NO" when the "7" key is
pressed.
NOTE:
The parameters stay in effect if you load a different
worksheet, or even if you quit your spreadsheet and restart
it later. The parameters will not be reset until you remove
GoalSeeker from memory (with the "REMOVE" command) or turn
your computer off.
MAXIMUM NUMBER OF ITERATIONS
The default value is 10.
Typically, GoalSeeker will find the solution in three iterations
(number of solutions tried). However, some of the more complex
spreadsheets may require more than 10 iterations to find a
solution.
NOTE:
The starting value of the solution is important. If the goal
has not been found in the maximum number of iterations, the
best value is chosen. You might try the goal seek again with
the new value.
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
Typically, fewer iterations are required if the starting number is
close to the solution.
The number of iterations may be set from 1 to 25.
PERCENT ERROR ALLOWED IN GOAL
The default value is .5%.
When the Goal value falls within this percent tolerance (plus or
minus), the goal is determined to be found. The default percent
error is one-half of 1%. GoalSeeker will usually find the answer
exactly; however, this percent error will allow for some
flexibility.
Example:
If .5% is the percent error in the goal and the goal value we
are looking for is 100, then a goal of 99.5 to 100.5 is
valid.
99.5 100 100.5
If the goal value we are looking for is zero (0), the percent
error is multiplied times 1 to determine the variance allowed (1
is used because zero times percent error is zero).
Example:
If .1% is the percent error allowed in the Goal and the goal
we are looking for is 0.0, then a goal of -.001 to +.001 is
valid.
-.001 0.0 .001
The percent error value may be entered up to 9 decimal places.
NOTE:
The user may enter any percent error including zero percent
(0%) error, however, if a zero percent error is used, the
goal value must match exactly to 15 decimal places.
PERCENT TO VARY INITIAL VALUE
The default value is 10%.
The starting value of the SOLUTION cell is multiplied times this
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
percentage to obtain the second value. This percentage is used to
make the first "guess" to solve the goal seeking problem.
The percent value can be within any range, including a minus
percentage.
In most cases, this percentage will have no effect on the outcome
of the solution. However, if the solution is bounded by a small
amount, the user may wish to restrict the second guess to say 1%.
Example:
If the starting value is 10 and the percentage is set to 10%,
the second value of the solution will be 11.
LOWER/UPPER BOUNDARY OF THE SOLUTION
The default value is -1.e99 to 1.e99 (or no bounds).
If you know the range of the solution, you may wish to limit the
bounds of the solution with this parameter.
Example:
If you know the solution is positive, set the lower bound
to 0.
Generally you will not need to set this parameter.
RECALC "N" TIMES BEFORE SOLUTION IS PICKED
The default value is 1.
This parameter is only useful on spreadsheets with a circular
reference.
Some spreadsheets are required to be executed "N" number of times
before the answers in the spreadsheet converge. You should know
the number required to make the goal value converge before you use
this option.
The Recalc "N" times may be set from 1 to 50.
MULTI-GOAL: STOP ON ERROR
The default value is "YES"
This parameter is only used for the "Multi-Goal" option. When
"Stop on error" = YES and the maximum number of iterations is
reached without finding a goal, the "Multi-Goal" option will stop
and issue its normal error message.
"Stop on error" = NO is useful if the user wants to control the
multi-goal with the spreadsheets macro capability. If the maximum
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
number of iterations is reached or any error occurs, the
multi-goal macro will be executed. If no macro exists, the next
multi-goal value will be executed.
If "Stop on error" = NO, no indication that an error has occurred
will be given.
MULTI-GOAL OPTION
The "Multi-Goal" option allows you to run a series of goal seeking
jobs at a time. When you press the "M" key (for "Multi-Goal") on
the GoalSeeker menu, the "Multiple Goals" window will be displayed
over your spreadsheet.
GoalSeeker MULTIPLE GOALS
Esc=cancel, F10=start multiple goal seek
To use multiple goals, a portion of your spreadsheet
should look similar to below - each cell is adjacent
Enter the cell location within your spreadsheet where
the cell C2 below would be located: ______________
(then press return; F10 to execute)
SOLUTION GOAL GOAL Results MACRO
Cell Cell Value Key (optional)
your H I J K
spread C2 D3 1234.23
sheet E5 E15 2672.89 MACRO R
F5 F15 0.0 MACRO T
MULTI-GOAL AND YOUR SPREADSHEET
Within your spreadsheet, you should set aside an area which will
describe the values required for GoalSeeker to operate. The area
should contain 4 columns (cells) of information. These 4 values
are on a single row and contain enough information for GoalSeeker
to perform one goal seek.
This area will describe the SOLUTION cell, the GOAL cell, the
desired goal value for the GOAL cell, and optionally, the name of
a user defined macro to execute after the goal has been found.
NOTE:
The word "MACRO" is a keyword to GoalSeeker.
RULES FOR MULTI-GOAL SPREADSHEET VALUES
The cell values may be upper or lower case (i.e., a23).
Cell values must be left justified(i.e., 'C9).
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Only one value per cell.
The goal value must be a numeric value.
The goal value may be in any numeric format (i.e., $1,234).
The keyword MACRO must be left justified in the cell.
A single space should separate the keyword MACRO and the
single Letter defining the macro (i.e., MACRO G).
TO OPERATE
To enter the Multi-Goal Option, press the "M" key from the
GoalSeeker menu. Next enter the cell location (which is the upper
left hand corner of your spreadsheet area), press <Enter> then
press the "F10" key to start the Multi-Goal goal seeking process.
There is no GoalSeeker limit as to the number of rows used in a
Multi-Goal operation.
Example:
The following example of Multi-Goal and macros demonstrates
how you can goal seek on "Sales" for each of 12 months to
find a goal of $17,000 in "TOTAL PROFIT" in cell L95.
A B C D E
13
14 Jan Feb Mar Apr
15 Sales 1,234 3,434 4,234 6,347
. . . . . .
. . . . . .
. . . . . .
299
300 B15 L95 17000 MACRO B
301 C15 L95 17000 MACRO C
302 D15 L95 17000 MACRO D
303
304 \B /CB15~B297~
305 \C /CC15~C297~
To start the above example, enter cell "B300" in Multi-Goal
Option.
Multi-Goal and Macros
The fourth parameter in your spreadsheet is an optional macro
name. When the keyword "MACRO" followed by a letter "A" thru "Z"
is in the fourth cell, after the goal is found, it will be
executed. This macro must be predefined in your worksheet.
Example:
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
R S T U V
21
22
23 A7 G19 123.33 MACRO I
24 A7 G19 34.51 MACRO K
25
27 \I /FStest1~
28 \K /PPG
To start the above example, enter "S23" in the Multi-Goal Option.
In the above example, the cell A7 is the SOLUTION cell, G19 is the
GOAL cell, the goal value is 123.33, the predefined MACRO I will
be executed after the goal 123.33 has been achieved, then the next
row (beginning with S24) will be executed.
The goal seeking process will stop on cell S25.
MACRO I is a 1-2-3 macro to do a "File Save test1".
MACRO K is a 1-2-3 macro to do a "Print Printer Go" (range
preset).
The macro executed by GoalSeeker can perform almost any function,
except as described in the next section.
EXAMPLES OF MULTI-GOAL MACROS
Save the spreadsheet
Print the solution and goal to a printer
Load a different worksheet
Change the goal value in multi-goal
Save the solution in another cell
Restore the original value
Change the worksheet equations
Change a worksheet value
NOT ALL MACROS ARE ALLOWED!
Macros which request input from the keyboard are NOT allowed to be
used with Multi-Goal. Macros such as "{?}", "\XL", and "\XN" can
not be used.
DISALLOWED 1-2-3 MACROS
{?} prompt for input
\XL prompt for input
\XN prompt for input
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NOTE:
No checking for the macro type is done in GoalSeeker. If any
of the above macros are used, the goal may not be found.
STOPPING THE MULTI-GOAL PROCESS
GoalSeeker will process each goal seeking request from top to
bottom, one row at time. When a blank, null, or invalid solution
cell is reached, the goal seeking process will stop.
STOP ON ERROR PARAMETER
The default parameter is to stop the goal seeking process if an
error occurs or if the maximum number of iterations has been
reached. You may set this error option within the Parameters
Option.
If the Parameter for Multi-Goal is "Stop on Error = NO", then
GoalSeeker will not stop on an error or if the maximum number of
iterations is reached. You can control the goal seeking process
and error trapping with your own user defined macros. See
Parameters Option.
REVIEW OPTION
The Review option is used to review the results of the last goal
seek operation. Each solution value, goal value, target goal
value, and the differences are displayed for each solution tried.
The Review option may be useful if GoalSeeker could not to find
the correct solution, or if you wish to more closely examine the
goal seeking process.
The Review window is overlayed on top of your spreadsheet. An
example of the Review window is shown below.
The following example is a squared equation (A1^2).
GoalSeeker REVIEW
Esc=cancel
# Solution Goal Actual Diff
--- ------------ ----------- ------------ -----------
1 12.000000000 144.0000000 4.0000000000 140.0000000
2 13.200000000 174.2400000 4.0000000000 170.2400000
3 6.4444444444 41.53086419 4.0000000000 37.53086419
4 2.0000000003 4.000000001 4.0000000000 .0000000012
The starting value of the solution cell was 12 and the starting
value of the goal cell was 144. The second solution value is
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
13.2, which is 10% of the starting value (12.00). The 10% value
is the "Initial starting percentage" as described in the
"Parameters" section.
The previous example proceeds through 4 iterations until our goal
of 4.0 was reached. In this example, you will notice that the
answer is not exact, but it is within our percent error allowed in
goal which is described in the "Parameters" section.
The Review window will hold approximately 13 numbers. If more
than 13 iterations are required to find the goal, the following
message will be displayed:
Press any key=next page, Esc=cancel
Press any key to see the results of the remaining iterations up to
25.
GOAL ERRORS
If the result of the calculated GOAL cell was in error or had a
value such as "ERR", "*******", or "NA", a message will be
displayed in the REVIEW window which states "ERROR in
Calculation". The solution value which caused the error will also
be displayed.
This example uses the @SQRT(A1) function in Lotus 1-2-3.
GoalSeeker REVIEW
Esc=cancel
# Solution Goal Actual Diff
--- ------------ ----------- ------------ -----------
1 4.0000000000 2.000000000 1.0000000000 1.000000000
2 4.4000000000 2.097617696 1.0000000000 1.097617696
3 -.0976176980 ERROR in Calculation
4 0.0 0.0 1.0000000000 -1.00000000
5 1.5574153941 1.247964500 1.0000000000 .2479645002
6 1.0000000001 1.000000000 1.0000000000 .0000000001
As you can see, GoalSeeker used a negative number for the third
try, which caused an error in the GOAL cell. (Square Root of any
negative number is an error).
When an "ERROR in Calculation" occurs, GoalSeeker must "guess" at
a value to clear the error. In the example above, the first
"guess" was zero.
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If the goal had not been found, this review may have given you
information to set parameters, such that the solution is always
positive.
PROBLEMS AND SOLUTIONS
The following is a list of situations which can arise while using
GoalSeeker and possible corrections to problems.
VARYING MORE THAN ONE ITEM
GoalSeeker will vary only one data item at a time to find a single
goal. However, you may want to see the result goal seeking would
have on many input variables at the same time. One way is to
average or "weigh" the input numbers.
For example, assume you have 12 monthly sales numbers and you want
to set a goal on the yearly profit number. To find the solution
for all twelve months, we could average.
Example:
If the 12 sales numbers are input data values, change each to
a formula cell. Set each input monthly sales number equal to
a formula (1: +G4/12, month 2: +G4/12, etc.) and vary G4 (the
SOLUTION cell). Now we can see the average for each month.
MULTIPLE SOLUTIONS
Under some conditions, there may be more than one solution to
achieve the desired goal value. The best example is a squared
equation (i.e. A1^2). If you are looking for a goal of 1, then
there are two answers: 1 and -1, because a minus one times a minus
one is still a plus one.
To solve this problem, you can:
1. Use a starting solution value close to what you believe
is going to be the final solution. Example, a negative
starting value in the above example would produce a -1
answer.
2. Limit the bounds of the solution using the Parameters
option. In the above example, set the lower bounds of
the solution to 0 to obtain a positive solution of 1.
It is possible to have three or more solutions to a desired goal.
If the
solution GoalSeeker found is not the solution you desire, set both
the lower and upper bounds of the solution to the range you
desire.
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SOLUTION NOT POSSIBLE
It is possible to request a goal value which simply cannot be
reached. The best example is again the squared equation A1^2. If
a goal value of -1 is requested, no solution will be found.
DISCONTINUOUS FUNCTIONS
A discontinuous function is one where an IF function (@IF in
Lotus) has changed the normal result of an equation. GoalSeeker
can solve this type of problem, however, many iterations may be
required.
Example:
EXPENSES = SALES * 9%
IF EXPENSES < 500 THEN EXPENSES = SALES * 3%
When EXPENSES changes from 499 to 500, a different equation is
used. Since the equation changed at 500, this would be a
discontinuous function.
SOLUTION CELL PROTECTED
If the solution cell is protected, a "Cell Protected" message will
be printed. You must unprotect the solution cell for GoalSeeker
to operate.
CANNOT LOAD WORKSHEET
GoalSeeker requires approximately 40k bytes of memory, which is
taken before you load your worksheet. If the memory size of your
worksheet is close to the memory size of your computer, you may
see a "memory full" error message produced by your spreadsheet
when you load your worksheet.
For GoalSeeker to operate on the worksheet, you will either have
to reduce the size of the spreadsheet or add more memory to your
computer. Memory can be added with an EMS board, for example.
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SOLUTION NOT BOUNDED
GoalSeeker will have a difficult time finding the correct answer
to an unbound solution. This is a solution where the answer does
not converge or the goal seems random.
REMOVE PROGRAM
The REMOVE program is used to remove GoalSeeker from memory.
GoalSeeker is a memory resident program which takes about 40k
bytes of overhead to operate. You may need to free that amount of
memory for other applications.
IMPORTANT
GoalSeeker must be the last memory resident program
loaded to remove it from memory.
At the DOS prompt, type "REMOVE" and then press the <Enter> key.
You should see the message "Unloading the product: GoalSeeker".
This indicates that GoalSeeker has been removed from memory and
the memory that it previously occupied has been freed.
If you run REMOVE and the message "Nothing found to unload"
appears, then GoalSeeker has already been removed from memory.
If you see the message "Another program intervenes", this
indicates that GoalSeeker was not the last memory resident program
loaded. Another memory resident program has been loaded after
GoalSeeker. To remove GoalSeeker from memory, you must first
remove the intervening program with that program's own remove
procedure.
NOTE:
Some memory resident utilities cannot be removed from memory,
such as the DOS commands MODE and PRINT. If you have loaded
either of these memory resident program after GoalSeeker, the
only way to remove GoalSeeker from memory is to re-boot your
system.
GOALSEEKER MESSAGES
The following GoalSeeker messages are in alphabetical order. An
explanation of each message follows.
"A GOAL VALUE MUST FIRST BE DEFINED"
You must define a goal value before you begin the goal seeking
operation. Move to the GOAL cell and press <Alt><Space> and then
press "G" key.
"ALREADY LOADED"
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
This message will be displayed if you attempt to load GoalSeeker
when it is already in memory. All of your parameters remain in
effect.
"ERROR - THE SOLUTION CELL IS NOT A FUNCTION OF THE GOAL CELL
(XX)"
OR
"ERROR - THE GOAL VALUE DID NOT CHANGE WHEN THE SOLUTION WAS
MODIFIED"
The goal value did not change when the starting solution value was
multiplied by the starting percentage. See the Parameters Option.
Check your equations to be certain that the SOLUTION cell is used
in calculating the GOAL cell. If it is, then be certain that
changing the solution value by the starting percentage will modify
the goal value. The change in this goal value is required for
GoalSeeker to operate.
"ITERATIONS MUST BE BETWEEN 1 AND 25"
Within the Parameters Option, the maximum number of iterations is
25.
"MAXIMUM NUMBER OF ITERATIONS REACHED"
GoalSeeker has reached the number of tries specified in the
Parameters Option and has stopped processing without finding the
desired goal. Some of your options are:
1. Try GoalSeeker again with the new starting value.
2. Increase the percent error in goal parameter.
3. Limit the bounds of the solution.
"NO MEMORY AVAILABLE FOR GOALSEEKER - NOT INSTALLED"
GoalSeeker was not installed on your computer when you typed GS at
the DOS prompt. GoalSeeker requires only 40k bytes of memory, but
not enough memory was available to install it. Check your memory
chips for errors or remove other memory resident programs from
memory.
"PRESS R KEY TO RESTORE ORIGINAL VALUE"
If the R key is pressed when this message appears, GoalSeeker will
automatically restore the beginning solution value to the
spreadsheet. This would be the value before the goal seeking
operation started.
"THE GOAL CELL MUST BE A CALCULATED (FORMULA) CELL"
When you are defining a target goal, the GOAL cell must contain a
formula. Refer to your spreadsheet users manual for the
definition of a formula. Example: +A1 is a calculated cell.
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GoalSeeker Users' Manual Copyright 1987 Brown Bag Software
"USE DOS 2.0 OR ABOVE"
GoalSeeker will only work with DOS version 2.0 or higher. You can
use the DOS command "VER" to find out what version of DOS you are
currently running. For more information on "VER", refer to your
DOS manual.
"YOU MUST BE WITHIN YOUR SPREADSHEET TO ACTIVATE GOALSEEKER"
If you press the <ALT><Space> to start GoalSeeker you, are
required to be in your spreadsheet. If you are in your
spreadsheet program and get this message, check the section of
this manual labeled "INSTALLING GOALSEEKER" to be certain that the
correct version of GoalSeeker is installed to match your spreadsheet.
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