python内置函数3-cmp()
Help on built-in function cmp in module __builtin__: cmp(...) cmp(x, y) -> integer Return negative if x<y, zero if x==y, positive if x>y. cmp(x, y) Compare the two objects x and y and return an integer according to the outcome. The return value is negative if x < y, zero if x == y and strictly positive if x > y. 中文说明:比较两个对象x和y,如果x < y ,返回负数;x == y, 返回0;x > y,返回正数。 版本:该函数只有在python2中可用,而且在python2所有版本中都可用。但是在python3中该函数已经被删减掉。 >>> cmp(3,4) -1 >>> cmp(56,34) 1 >>> cmp(a,a) Traceback (most recent call last): File "<stdin>", line 1, in <module> NameError: name 'a' is not defined >>> cmp('a','a') 0 >>> cmp('abc','cbd') -1