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(49G/50g) Shortest code to increment a variable? - acser - 04-20-2023 11:50 AM
I can think of trivial code like this to increment variable A by one:
A 1 + ‘A’ STO
Are there shorter, faster, more elegant ways to do this?
Thanks,
A
RE: (49G/50g) Shortest code to increment a variable? - Marco Polo - 04-20-2023 12:21 PM
(04-20-2023 11:50 AM)acser Wrote: I can think of trivial code like this to increment variable A by one:
A 1 + ‘A’ STO
Are there shorter, faster, more elegant ways to do this?
Thanks,
A
1
'A'
STO+
(also available STO- STO* STO/)
or
'A'
INCR
(INCR and DECR increments and decrements by 1 and returns new value)
You can find all commands in menu PRG-->MEM-->ARITH
RE: (49G/50g) Shortest code to increment a variable? - John Keith - 04-20-2023 12:38 PM
Note that all three of these methods are significantly slower than keeping the value represented by A on the stack rather than in a variable. Even if the value is on a higher stack level, e.g. ROT 1. + UNROT is still faster than INCR or STO+. Also use real numbers rather than exact integers if possible.
These optimizations are not important if the incrementing only occurs a few times in the running of the program but they should be considered if the incrementing occurs inside a loop, which it usually does.
RE: (49G/50g) Shortest code to increment a variable? - acser - 04-20-2023 07:11 PM
Thank you all. Very useful.
RE: (49G/50g) Shortest code to increment a variable? - Gil - 04-20-2023 08:45 PM
Note also that STO+
can be used with a variable that contains a list.
Suppose you have done {1 2 3} 'A' STO.
Then try 20 'A' STO+
and press A
to see the new list A {20 1 2 3},
with the number added as the first element of the list A.
Try now with "test" 'A' STO+
and press A
to see the new list A {"test" 20 1 2 3}.
Instead of a string,
you could have a variable name such as 'B':
Try 'B' 'A' STO+
and press A
to see the new list A {B "test" 20 1 2 3}.