User guide

13–24 Programming Techniques
Program Lines:
(In RPN mode)
Description:
  
This routine collects all known values in three
equations.
 "!1
1
L2
2
Prompts for and stores a number into the variable
addressed by
i.
   L
Adds 1 to i and repeats the loop until i reaches
13.012.
 ! 
 ! 
When i exceeds the final counter value, execution
branches back to A.
Label J is a loop that completes the inversion of the 3
×
3 matrix.
Program Lines:
(In RPN mode)
Description:
  
This routine completes inverse by dividing by
determinant.
 !ª1
1
L2
2
Divides element.
   L
Decrements index value so it points closer to A
 ! 
Loops for next value.
 !
Returns to the calling program or to
 !
.
Equations with (i)
You can use (i) in an equation to specify a variable indirectly. Notice that
1L2
2
means the variable specified by the number in variable i (an indirect reference),
but that i or
1L2
means variable i.
The following program uses an equation to find the sum of the squares of variables
A through Z.