HP 15c Scientific manual Conditional Tests

Section 8: Program Branching and Controls 91

of this loop can be controlled by a conditional branch, an ¦ instruction (written into the loop), or simply by pressing any key during execution (which stops the program).

Conditional Tests

Another way to alter the sequence of program execution is by a conditional test, a true/false test which compares the number in the X-register either to zero or to the number in the Y-register. The HP-15C provides 12 different tests, two explicit on the keyboard and 10 others accessible using

Tn.*

1.Direct: £and ~.

2.Indirect: T n.

n	Test	n	Test
0	x ≠ 0	5	x = y
1	x > 0	6	x ≠ y
2	x < 0	7	x > y
3	x ≥ 0	8	x < y
4	x ≤ 0	9	x ≥ y

*Four of the conditional tests can also be used for complex values, as explained in section 11 on page 132.