Python cmp() function

Question

Hello I was trying to compare two tuples in python using the cmp() function But there was an error wich is the following:

NameError: name 'cmp' is not defined

my Code:

myStupidTup = ("test",10,"hmm",233,2,"am long string")
mySmartTup = ("test",10,233,2)
print(cmp(myStupidTup, mySmartTup))

As the error message clearly states: `cmp` is not defined. What is your question? — Asocia, Dec 10 '20 at 13:29
`cmp()` function is only in python 2.x. `cmp()` does not work in python 3.x. — Hirusha Fernando, Dec 10 '20 at 13:30
The built-in `cmp` function of Python 2 was dropped in Python 3. — Klaus D., Dec 10 '20 at 13:31

abhigyanj · Accepted Answer · 2020-12-10T13:53:13.513

The cmp function is only in Python 2.x. As mentioned in the official Python documentation:

The cmp() function should be treated as gone, and the __cmp__() special method is no longer supported. Use __lt__() for sorting, __eq__() with __hash__(), and other rich comparisons as needed. (If you really need the cmp() functionality, you could use the expression (a > b) - (a < b) as the equivalent for cmp(a, b).)

The cmp equivalent in Python 3.x is:

def cmp(a, b):
    return (a > b) - (a < b)

Note: Your tuples (myStupidTup and mySmartTup) don't support comparison. You will get a TypeError if you run it: TypeError: '>' not supported between instances of 'str' and 'int'

Python cmp() function

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