14

Solving and Integrating Programs

Solving a Program

In chapter 7 you saw how you can enter an equation — it's added to the equation list — and then solve it for any variable. You can also enter a program that calculates a function, and then solve it for any variable. This is especially useful if the equation you're solving changes for certain conditions or if it requires repeated calculations.

To solve a programmed function:

1.Enter a program that defines the function. (See "To write a program for SOLVE" below.)

2.Select the program to solve: press Wlabel. (You can skip this step if you're re–solving the same program.)

3.Solve for the unknown variable: press variable.

Notice that FN= is required if you're solving a programmed function, but not if you're solving an equation from the equation list.

To halt a calculation, press ‡or g. The current best estimate of the root is in the unknown variable; use Što view it without disturbing the stack. To resume the calculation, press g.

To write a program for SOLVE:

The program can use equations and ALG or RPN operations — in whatever combination is most convenient.

1.Begin the program with a label. This label identifies the function that you want SOLVE to evaluate (/label).

Solving and Integrating Programs 14–1