if "16" > "13": print("a")
if "8" > "15": print("b")
This code will print "a b" in the console. Why does the first statement work as intended and the second doesn't?
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Strings are compared in alphabetical order; the fact that all of your characters are digits doesn't magically cause the strings to behave like numbers. – jasonharper Apr 26 '21 at 19:19
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Define "intended" ? – DeepSpace Apr 26 '21 at 19:21
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more about in [this answer](https://stackoverflow.com/questions/4806911/string-comparison-technique-used-by-python) – Rafael Dourado D Apr 26 '21 at 19:21
2 Answers
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In Python, the > and < operators are implemented using a class's underlying __cmp__ magic function, the logic of which differs by class.
The logic for numbers is to compare the signed value, e.g. 12.6 >10 is true, and -4 > -33.02 is true, in the normal mathematical sense.
The logic for strings is to compare each character, left to right, based on the ordinal value of each character, e.g. 'apple' > 'banana' is false because ord('a') is 97 and ord('b') is 98, so 97 > 98 is false. Likewise '8 > '15' is true because ord('8') is 56, and and ord('1') is 49, so 56 > 49 is true.
Python doesn't convert strings-of-digits to numbers before comparing.
Chris Johnson
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Because 8 (first digit) is greater than 1 (first digit)... you are comparing strings, not integers.
Do you want to compare numbers? Do the same without the quotes:
if 16 > 13: print("a")
if 8 > 15: print("b")
mcsoini
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