A problem with str VS int.

[Roel Schroeven]

Op 12/12/2023 om 9:22 schreef Steve GS via Python-list:
> With all these suggestions on
> how to fix it, no one seems to
> answer why it fails only when
> entering a two-digit number.
> One and three work fine when
> comparing with str values. It
> is interesting that the
> leading 0 on a two digit
> worked.  Still, one digit and
> three digit work but not two.

Three-digit numbers work because you're comparing to another three-digit 
numbers. When two integer numbers have the same number of digits, their 
lexicographical ordering matches their numeric ordering.

One-digit numbers don't work fine:

 >>> "5" < "400"
False

even though we can construct cases where it seems as if they do:

 >>> "1" < "400"
True

Two-digit numbers sometimes seem to work:

 >>> "30" < "400"
True

But other times clearly don't work:

 >>> "50" < "400"
False

String comparison first looks at the first characters of both operands. 
If they are different (as in the examples above), their ordering is used 
regardless of all the other characters that come after, and regardless 
of the length of the string. Try working through some examples (make 
sure to pick examples with a wide variety of first digits) and you'll 
see why it sometimes seems to work, but very unreliably.

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