HP 15c Collector's Edition User Manual

104 Section 9: Subroutines
Example: Nesting. The following subroutine, labeled “.4”, calculates the
value of the expression

x
2
+y
2
+z
2
+  t
2
as part of a larger calculation
in a larger program. The subroutine calls upon another subroutine (a
nested subroutine), labeled “.5”, to do the repetitive squaring.
The program is executed after placing the variables t, z, y, and x into the
T-, Z-, Y-, and X-registers.
Keystrokes
´ b .4
Start of main
subroutine.
| x
x
2
.
G .5
Calculates
y
2
and
x
2
+
y
2
.
G .5 1
Calculates
z
2
and
x
2
+
y
2
+
z
2
.
G .5 2
Calculates
t
2
and
x
2
+
y
2
+
z
2
+
t
2
.
¤ 3
√ x
2
+ y
2
+ z
2
+ t
2
| n
End of main subroutine;
returns to main program.
´ b .5
Start of nested
subroutine.
®
| x
Calculates a square and
adds
it to current sum of
squares.
+
| n
End of nested sub
-
routine;
returns to main subroutine.
If you run the subroutine (with its nested subroutine) alone using x = 4.3,
y = 7.9, z = 1.3, and t = 8.0, the answer you get upon pressing G .4 is
12.1074.

HP 15c Collector's Edition Specifications

General

Brand	HP
Model	15c Collector's Edition
Category	Calculator
Language	English