HP 33s User Manual

Page 193

Programming

Techniques

13–9

Flags 0, 1, 2, 3, and 4

have no preassigned meanings. That is, their

states will mean whatever you define them to mean in a given program. (See
the example below.)

Flag 5,

when set, will interrupt a program when an overflow occurs within

the program, displaying #$ and

An overflow occurs when a

result exceeds the largest number that the calculator can handle. The largest
possible number is substituted for the overflow result. If flag 5 is clear, a
program with an overflow is not interrupted, though #$ is displayed
briefly when the program eventually stops.

Flag 6

is automatically set by the calculator any time an overflow occurs

(although you can also set flag 6 yourself). It has no effect, but can be tested.

Flags 5 and 6 allow you to control overflow conditions that occur during a
program. Setting flag 5 stops a program at the line just after the line that
caused the overflow. By testing flag 6 in a program, you can alter the
program's flow or change a result anytime an overflow occurs.

Flags 7, 8 and 9

control the display of fractions. Flag 7 can also be

controlled from the keyboard. When Fraction–display mode is toggled on or
off by pressing

{

, flag 7 is set or cleared as well.

Fraction–Control Flags

Flag

Status

Clear

(Default)

Fraction display
off; display real
numbers in the
current display
format.

Fraction
denominators not
greater than the
/c

value.

Reduce fractions
to smallest form.

Set

Fraction display
on; display real
numbers as
fractions.

Fraction
denominators are
factors of the /c
Value.

No reduction of
fractions. (Used
only if flag 8 is
set.)