Description

To learn more about Ewe please read the introduction on the Bray Mobile Applications page.

The formulas of FormulaCalc:

• Use common algebraic expressions with the normal multiply before add rules.
• Can have up to 26 inputs from stored data.
• Can store results in up to 26 storage locations.
• Can use trigonometric, logarithmic, and other algebraic and control functions.
• Can be input by pen or from a selected file.

It can be used as a simple calculator, or one to compute complicated routines. We hope you find FormulaCalc useful.

About This Documentation

For a quick start read Installation and Quick Start.
Then after trying it out please return to this documentation to learn all of the features.

Documentation Sections

• Installation (Must Read)
• Quick Start (Must Read)
• Using FormulaCalc
  • The Menu Actions
  • Storing Routines
  • Operators and Functions
  • Default Control Settings
  • Output Format Control
  • Programmed Input
  • Operator Calculation Order
  • Examples
• Contact Info
• Version Changes

Installation

Installation Steps

1. Install the the Ewe VM.
2. Copy FormulaCalc.ewe to your computer(s).

Step 1

The first thing to do is to install the Ewe VM on your computer(s), if not already installed. Follow the instruction found on the Ewe Download and Installation Page for your computer(s). The Ewe installer will create directories on your computer and put the Ewe VM files in them.

After Ewe is installed find the Ewe directory. For example, in a Windows Desktop it will be where you told the installer to install it, and in the Pocket PC it will (probably) be in \Windows\StartMenu\Programs\Ewe. Specifically, it is the directory in which you find 'ewe.ewe'.
If you put all of your applications in this directory, when you add additional applications from Bray Mobile Applications common files can be shared.

Step 2

There is no installer for FormulaCalc.ewe. It can be put in any directory of your choice. However it is recommended that you put it in the directory with the Ewe VM you found in Step 1.

Once you find the proper directory copy FormulaCalc.ewe into that directory in what ever manner you copy files to your computer.

There is also no uninstaller for FormulaCalc. It does not use the operating system registry, so nothing is hidden. To remove FormulaCalc, simply delete: FormulaCalc.ewe, and any *.fmc formula files which you created.

Note: No matter what Regional settings are used on your computer(s), FormulaCalc always uses the '.' (period) as the decimal point, the ',' (comma) as the formula argument and data separator, and the ";" (semicolon) as the end of formula.

FormulaCalc should be ready to run. Find FormulaCalc.ewe with your File Explorer, click on it to try it out! Soon after you try out FormulaCalc and find it working, you should read the Quick Start which follows.

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Quick Start

• The Menu Header -- the Menu Selector, and the current input source.

• The Input Area -- the clear upper box. The Input Area is also called the Pen Area.

• The Output Area -- the clear lower box.

• The Button Trailer -- the five control buttons.

The Button Trailer

• Clear -- clears the Output Area (one tap) and Input Area (double tap). The Clear button is also a way to exit an open window and return to the Input/Output Area window.

• Compute -- computes the value of the active routine and displays it in the output area. If you press Compute at first nothing will happen because the Input Area is empty.

• Reg -- pops up a new window showing the values of the 26 registers A - Z.
  The values are changed by tapping a value and modifying it.

• Source -- toggles the active input between the Input Area (i.e. Pen Area) formulas (i.e. routine) and the routine selected using the Open button. Pressing this button at will change the active routine and display "Pen Active" and "Open Routine Active" in the upper right.

• Open -- opens one of the stored routines from a selected formula file. Upon first tap of Open the 'File Chooser' is opened allowing selection of the desired file containing FormulaCalc routines. The next time Open is tapped routines from the same file are displayed, unless the Menu/GetNewFile menu item has been selected. By convention the formula files are given the file extension of .fmc, but may be any desired file type (extension).

If you want to use FormulaCalc as a simple calculator:

• Tap the upper left of the Input Area,
• Enter a formula -- e.g. 123 * 4,
• Tap Compute,
• The result is displayed in the Output Area.

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Your First Routine

For this first trial we clear both the Output Area and Input Area by tapping the Clear button two times. (Before the Input Area is cleared a permission box pops up.)
Now with the pen and enter:   3*4-7/3   then press Compute.
The value 9.667 will appear in the output box. An "ordinary" calculator would have displayed 1.666... because it would use a left to right calculation rather than computing 3*4 then 7/3 and then subtracting as we understand algebraic formulas.

Now on the second input line enter: a=2; sr(a); a^2 then press Compute. The output box now displays 4 lines: 9.667   9.667   1.412   4.00
Press the Compute and Clear buttons several times to see what happens.

Next press the Reg button. You will see that the A register now has 2.00 and R has 4.00. That is because you stored 2 in A, and R is the result register which contains the last computed value 4.00.
Using the pen select register G, enter 20 and press Done. Now G contains 20. Press Reg again. This returns FormulaCalc to the Input/Output areas. On the third input line enter G to the end of your routine.
Your routine should now read:

1. 3*4-7/3
2. a=2; sr(a); a^2
3. g

You are now an expert!

To prove that, see if you understand the example on the right.

A better formatted answer version of this is shown below.

Note: To edit input in the Input Area you can hold down the pen to pop-up a Copy/Cut/Paste action box.

Allowable Formula Objects

The definitions for these are given below, but it is now time for you to try FormulaCalc for yourself.
When you get puzzled or you want to save a routine for future use, come back. It's all explained below.

This is the end of Quick Start.

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Using FormulaCalc

Menu Actions

• View File -- will pop up a window showing the open routine.

• File to Pen -- will copy the open routine to the Input Area (Pen Area).

• Export Pen -- will copy the routine in the Input Area to the end of the open Formula File. It will be titled #Exported Routine.

• Import Reg -- restore the Registers to that previously exported. This brings up a 'File Chooser' for selection of the desired exported register file.

• Export Reg -- saves the current Registers to a file. This brings up a 'File Chooser' for naming a file and saving the contents of the Registers to that file. The saved file is in the .CSV format so it is suggested that the extension be .CSV, but may be any desired file type (extension).

• Debug On -- this overrides a sr:n setting to cause the assignments to registers to be displayed. This actually toggles the override of sr:n off and on.

• Clear Regs -- this clears all registers to 0.

• GetNewFile -- this forces Open to display the 'File Chooser' so that a new Formula File can be selected.

• About   This is the usual About information. It tells you the version of FormulaCalc you have installed.

• Quit   The obvious Quit selection. You can also quit using the upper right hand X. In either case you will asked if you with to save the current settings (i.e. Input Area and Registers) of FormulaCalc for next usage start-up.

  

• Functions -- this pops up a window to allow you to copy a function to the end of the Input Area. This pop-up window is shown at the right.

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Storing Routines

A Formula File has the following format:

• Each routine starts with a '#' sign in column 1 followed by the name. E.G. #Compound Interest.
• A routine is of the form: formula followed by ; (and/or new line) followed by formula .....
  The routine is terminated by one or more blank lines.
  All space characters within a formula are ignored.

Following is an example Formula File with two routines:

    #Compound Interest
    [Reg: I interest, P principle]
    [N years, M periods per year]
    dd:2
    (1+i/m)^(m*n)*p

    #Future Annuity
    dd:2; ((1+i/m)^(m*n)-1)/(i/m)*p

The second routine in the Formula File is Future Annunity.
As many routines as desired may be in a Formula File. Each routine must start with a '#' in column 1.

See Programmed Input for control over the register values.

It is recommended that you create a Formula File, even if it is empty, in the directory with FormulaCalc.ewe.
Having such a file allows you to check out routines written in the Input Area with the pen and then export them with Menu/Export Pen when you have them working to your satisfaction.

Warning:

1. Be sure to you choose the Formula File using Open even if there is nothing to open before you try to export the Input Area. As mentioned above exported routines are given a default name of #Exported Routine. Later you can edit the Formula File to give each a correct unique name.
2. If you open a Formula File which has more than routine named '#Exported Routine' only the first such routine in a Formula File will be opened. Any other such routines will be ignored until you give them a unique name(s).

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Operators and Functions

arithmetic:

  +

addition -- e.g. 4 + 8     result: [12]

  -

negation -- e.g. -4 or subtraction e.g. 5 - 2.02     [2.98]

  *

multiplication -- e.g. 12 * 6     [72],     121 * -7     [-847]

  /

division -- e.g. 36 / 4.321     [8.3314]

  ^

x to power y -- e.g. 2 ^ 3     [8]

  %

remainder of x divided by y -- e.g. 30.25 % 5     [0.05],     30.25 % 1     [0.25] the fractional part

arithmetic:

  sr()

square root -- e.g. sr(2)     [1.1414]

  sq()

square -- e.g. sq(2)     [4]

  ln()

natural logarithm -- e.g. ln(3)     [1.0986]

  log()

base 10 logarithm -- e.g. log(1000)     [3]

  abs()

absolute value -- e.g. abs(-654)     [654]

  int()

integer part -- e.g. int(30.25)     [30]

  pi

constant pi -- e.g. pi * 2     [6.283185307]

  deg

constant 180/pi -- e.g. deg     [57.29577951]

  rad

constant pi/180 -- e.g. rad     [0.017453292]

trigonometric:

  sin()

sine -- e.g. sin(1)     [0.8415]

  cos()

cosine -- e.g. cos(1)     [0.5403]

  tan()

tangent -- e.g. tan(1)     [1.5574]

  asin()

arcsine -- e.g. asin(1)     [1.5708]

  acos()

arccosine -- e.g. acos(1)     [0.0000]

  atan()

arctangent -- e.g. atan(1.5574)     [1.0]

assignment:

  =

register store -- e.g. a = 2     [2] -- a cumulative example

  +=

add and store -- e.g. a += 13     [15]

  -=

subtract and store -- e.g. a -= 9     [6]

  *=

multiple and store -- e.g. a *= 3     [18]

  /=

divide and store -- e.g. a /= 3     [6]

decision -- used in if(,,):

  <

less than -- e.g. a < 10

  <=

less or equal -- e.g. a <= q

  ==

equal -- e.g. 20 == w

  >=

greater or equal -- e.g. t >= s

  >

greater than -- e.g. d / 3 > 10 * 7 + a

string:

  " "

string -- e.g. "answer is:"     [answer is:]

  st()

convert number to string -- e.g. st(654)     [654]

comment:

  #

non-printing comment to end of line -- e.g. sin(30); # this is the angle     [0.500]

  [ ]

non-printing comment -- e.g. [debug line]     [ ]

programmed input -- e.g. [@t,Temperature]     [Opens a dialog box]
See Programmed Input

control:

  if(,,)

select -- e.g.   a=18;   if (a<10, a, a/3)     [6]     or a=9     [9]

  dd:

decimal digits (0-15) -- e.g. dd:4; 1234.5;     [1234.500]

  ds:

display string

    ds:s; display string start

    ds:e; display string end

e.g. ds:s; "The answer is: "; st(2^4); ds:e     [The answer is: 16]
See Output Format Control

  se:

exponent to display scientific notation (0-15) -- e.g. se:4     [ ]

  sr:

show register assignments (y or n) -- e.g. sr:y     [ ]

  cc:

compution control

    cc:d trig formulas use degree cc:d -- e.g. cc:d; sin(2)     [0.034899]

    cc:r trig use radians -- e.g. cc:r; sin(2)     [0.909297]

    cc:t scientific notation trim trailing zeros -- e.g. dd:6; se:2; cc:t; 1234;     [1.234e3]

    cc:z scientific notation show trailing zeros -- e.g. dd:6; se:2; cc:z; 1234;     [1.234000e3]

Notes: The se: value determines at what exponent value the notation is switched between fixed to scientific notation.
The cc:t or cc:z determines if trailing 0's in scientific notation are displayed.
More examples:

• When dd:2; se:5; 12345.6789 will display as 12345.68, but 123456.789 will display as 1.23e5
• When dd:2; cc:t; 10000.001 will display as 10000.00, but 100000.001 will display as 1e5
• When dd:2; cc:z; 100000.001 will display as 1.00e5

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Default Control Settings

• Degrees/Radians -- cc:d - Degrees
• Decimal digits -- dd:4 - 4
• Display scientific notation -- se:5 - when exponent e±5 or more
• Show register values -- sr:n - No
• Display trailing zeros -- cc:t - No (perform Trim)

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Output Format Control

Strings cannot be assigned to a letter.

Instead writing the poorly formatted routine for converting Celsius to Fahrenheit and vise versa, write the routine as follow:

[F to C and C to F. Input w]
dd:1;
ds:s; st(w);" F is "; st((w-32)*5/9); " C" ds:e;
ds:s; st(w);" C is "; st(w*9/5+32); " F"; ds:e

Check it out.

Note: Numeric values not converted to a string by st() are displayed immediately, i.e. not delayed until the ds:e. Consider:

ds:s; w=10; st(w); " F is "; st((w-32)*5/9); " C"; ds:e -- Displays: 10.0000 F is -12.2222 C, but
ds:s; w=10; w; " F is "; (w-32)*5/9; " C"; ds:e -- Displays: 10.0000-12.2222 F is C

Programmed Input

To request the user to input a register value, place the follow construct(s) at the end of a line. It has the following line. The general construct is that of a non-printing comment []:

'[@' register letter, prompt ']', for example:
[@w,Temperature].

A dialog box will open to allow the user to enter a value. The current value of the register will be displayed and highlighted.

The above routine for converting Celsius to Fahrenheit is shown next with a programmed input command.

[F to C and C to F. Input w]
[@w,Temperature]
dd:1; ds:s
st(w);" F is "; st((w-32)*5/9); " C"
ds:e; ds:s
st(w);" C is "; st(w*9/5+32); " F"
ds:e

• To indicate it is a programmed input request rather than a simple non-printing comment it starts with a '@'.
• FormulaCalc processes each line as a unit. That is, all statements in a line are acted upon without interruption. This means that a request to put a value in a register will not be completed until after the line ends.
  As an example of this, consider this two line routine:

  a=1; b=2; [@a,A register]; a; b;
  [@a,A register]; a=1; b=2; a; b;
  

  Regardless the value the user entered the result is: 1 and 2 for both the first and second line.
  Also, if a routine is only one line, any requested programmed input will have no effect!
• Only one Programmed Input Comment per line will be acted upon.

Operator Calculation Order

Group computation order:

First:	sr()   sq()   ln()   log()   int()   pi   sin()   cos()   tan()   asin()   acos()   atan()   if(,,)   deg   rad   <   <=   = =   >=   >
Second:	*   /   ^   %;
Third:	+   -
Last:	=   +=   -=   *=   /=
Not Combined:	dd:   sr:   se:   cc:   " "   [ ]   ds:   st()

Example:

          a = 10; deg                                          Left to right
          b = 2 * 3 + 5 * sin(a + 30) ^ 2 - 9 * (5 + 7)
              |   |   |     |  \   /    |    |    \  /
              |   |   |     |   40     /     |     12          Compute inside ()'s 1st
              |   |   |      \  /     /      |      |
              |   |   |      0.64    /       |      |          Then things in First
               \ /     \      /     /         \    /
                6        3.21      /            108            Then Second (leftmost)
                 \        \       /             /
                  \         10.33              /               And Second Again
                   \        /                 /
                     16.33                   /                 Then Third (leftmost)
                          \                 /
                                 -91.67                        And Third Again
          Finally the assignment

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Examples

Example 1:
This example shows the use of arithmetic assignments to registers, and iteration.

    #Powers of 2		Routine title
    sr:y			Show register store assignments
    u += 1; v *= 2

Example 2:

This example shows the use of the int() function (i.e. whole number extraction).
Julian Date was defined by astronomers to have a uniform date code independent of the calendar. It makes taking the difference between 2 dates easy. (See note below.)

    #Julian Date
    sr:n; dd:2; se:10
    i=int(z/100); i=2-i+int(i/4)
    int(365.25*z)+int(30.6001*(x+1))+y+1720994.5+i

Note: A Julian Date is defined to start at noon and show the fraction of a day. So to be accurate the day in y should be a day and a fraction. If y was 15.5 then noon on October 15, 1999 is the start of Julian Day 2451467.00
This routine is only accurate for the Oregonian calendar. A modification of this routine must be made for dates before October 15, 1582.

Example 3:

This example is really too complicated but it shows the use of the if(,,) function, and it shows how to encode 3 numbers into 1. It produces the calendar date for an Julian date, and show the fraction of a day to two decimal places.

    #Julian Calendar					Routine Title -- a comment
    dd:6; se:10; sr:n					6 decimal digits, scientific notation if exponent >= 10, no register values
    i=int((z+1-1867216.25)/36524.25);			number of centuries
    i=z+1+i-int(i/4);i=i+1524;				leap days
    j=int((i-122.1)/365.25)				a year value
    m=int(365.25*j); k=int((i-m)/30.6001)
    i=i-m-int(30.60001*k)				day of the month
    m=if(k<13.5,k-1,k-13);				month number
    if(m>2.5,j-4716,j-4715)+(m+i/100)/100		answer dependent on month value

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Contact Info

The Bray Palm OS Page can be found at: http://davidbray.org/palm/

Registering

This archive may be freely redistributed, provided it is made available only in its complete, unmodified form with no additional files and for noncommercial purposes only. Any other use must have prior written authorization from David W. Bray.

Unauthorized commercial use includes, but is not limited to:

• FormulaCalc itself as a product for sale.
• Accompanying a product for sale.
• Accompanying a magazine, book or other publication for sale.
• Distribution with 'Media', 'Copying' or other incidental costs.
• Available for download with access or download fees.

Disclaimer

Foot Notes

¹ Ewe is developed by Michael L Brereton. We are indebted to him for his outstanding software product and making it freely available. Thank you Michael!

Program Changes in Version 1.1

1. Added programmed input (V1.1 Bld:511)
2. Added horizontal scroll bar in the Input Area (V1.1 Bld:511)

To be sure that your version is up-to-date check the Bld: number in the current description of Riseset at: http://davidbray.org/mobile/