OpenWindows User's Guide

Creating and Saving a Function

Note that when you enter a value for a new function, you must type the keyboard equivalents in the Value field. To display the keyboard equivalents for each Calculator key, click SELECT on the Keys button.

The following example describes how to create and save a function that adds together two numbers taken from memory registers, and stores the result in another memory register.

  1. Choose Enter Function from the Fun key menu.

    The Enter Function pop-up window is displayed.

  2. Type in the number of the function you wish to add or replace in the Function No: field.

    The function number must be in the range 0 through 9.

  3. Type a function name in the Description field, for example, addition.

  4. Type a function into the Value field.

    To add the numbers in Memory Registers 1 and 2, and store the sum in Register 5, type R1+R2=S5. R1 means "R[etrieve] register 1," R2 means "R[etrieve register] 2," and S5 means "S[tore] into register 5." See Table 8-1 at the end of this chapter for the keyboard equivalents (such as R and S) that you can use when creating your functions.

    When you create your own functions, if you want to use a function from one of the function windows (that is, the Financial, Logical, or Scientific windows), make sure to include a command to change modes. For example, if you want to retrieve the contents of memory register 3 and get the factorial value of it, R3! will not work, because you need to change to Scientific mode before retrieving the factorial. Instead, use R3Ms!Mb. This function translates correctly to "Retrieve the contents of memory register 3, change mode to Scientific mode, get the factorial value, and change mode back to Basic mode."

  5. Click SELECT on the Enter Function button to store the new function in your .calctoolrc file and add it to the Functions menu.

    To use the new function, choose it from the Functions menu.

    When creating functions, remember that calculations are performed from left to right, with no arithmetic precedence. For example, the calculation 2 + 3 * 4 as performed by the DeskSet Calculator gives a result of 20. The same equation performed with canonical arithmetic precedence would give a result of 14. This can be achieved with the Calculator by using parentheses: 2 + (3 * 4)