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+--- Thread: SUBSTR indexes in free42 (/thread-17300.html)
SUBSTR indexes in free42 - mtern - 07-31-2021 01:01 PM
Hello, playing with the new string functions in free42 I notice that it seems SUBSTR uses an Y index starting from 0, while the X index starts from 1.
So to get the Nth character of a string or element of a list, you have N-1 in Y and N in X
Is it the expected behaviour?
Or maybe the intepretation is different: SUBSTR takes element from Y included to X excluded?
As a simple exercise, this is a reusable routine to get the nth string character or list element:
LBL "NTH"
FUNC 21
RCL ST X
1
-
X<>Y
SUBSTR
RTN
thank you
Mark
RE: SUBSTR indexes in free42 - Albert Chan - 07-31-2021 03:50 PM
(07-31-2021 01:01 PM)mtern Wrote: Or maybe the intepretation is different: SUBSTR takes element from Y included to X excluded?
Yes. String index is 0-based, end excluded → string length = end - begin
RE: SUBSTR indexes in free42 - mtern - 08-01-2021 03:48 PM
(07-31-2021 03:50 PM)Albert Chan Wrote:(07-31-2021 01:01 PM)mtern Wrote: Or maybe the intepretation is different: SUBSTR takes element from Y included to X excluded?
Yes. String index is 0-based, end excluded → string length = end - begin
Thank you for the clarification.
Mark