HP 33S - Tests of Comparison (X?Y, X?0)

Programming Techniques
13–7
File name 33s-E-Manual-1008-Publication(1st).doc Page : 386
Printed Date : 2003/10/8 Size : 13.7 x 21.2 cm

Flag tests. These check the status of flags, which can be either set or clear.

Loop counters. These are usually used to loop a specified number of
times.
Tests of Comparison (x?y, x?0)
There are 12 comparisons available for programming. Pressing
¹ ¬
or
º 
displays a menu for one of the two categories of tests:

x
?
y for tests comparing x and y.

x
?
0 for tests comparing x and 0.
Remember that x refers to the number in the X–register, and y refers to the number
in the Y–register. These do not compare the variables X and Y.
Select the category of comparison, then press the menu key for the conditional
instruction you want.
The Test Menus
x
?
y x
?
0
{
≠
} for x
≠
y
?
{
≠
} for x
≠
0
?
{
≤
} for x
≤
y
?
{
≤
} for x
≤
0
?
{
<
} for x
<
y
?
{
<
} for x
<
0
?
{
>
} for x
>
y
?
{
>
} for x
>
0
?
{
≥
} for x
≥
y
?
{
≥
} for x
≥
0
?
{

} for x=y
?
{

} for x=0
?
If you execute a conditional test from the keyboard, the calculator will display

or

.
Example:
The "Normal and Inverse–Normal Distributions" program in chapter 16 uses the
x
<
y
?
conditional in routine T: