Python 3 – 比较运算符示例

这些运算符比较它们两侧的值并确定它们之间的关系。它们也被称为比较运算符。

假设变量 a 值为10，变量 b 值为20，则 −

运算符	描述	示例
`==`	如果两个操作数的值相等，则条件成立。	(a == b)不成立。
`!=`	如果两个操作数的值不相等，则条件成立。	(a!= b)成立。
`>`	如果左操作数的值大于右操作数的值，则条件成立。	(a > b)不成立。
`<`	如果左操作数的值小于右操作数的值，则条件成立。	(a < b)成立。
`>=`	如果左操作数的值大于或等于右操作数的值，则条件成立。	(a >= b)不成立。
`<=`	如果左操作数的值小于或等于右操作数的值，则条件成立。	(a <= b)成立。

示例

假设变量 a 值为10，变量 b 值为20，则 −

#!/usr/bin/python3

a = 21
b = 10

if ( a == b ):
   print ("Line 1 - a is equal to b")
else:
   print ("Line 1 - a is not equal to b")

if ( a != b ):
   print ("Line 2 - a is not equal to b")
else:
   print ("Line 2 - a is equal to b")

if ( a < b ):
   print ("Line 3 - a is less than b" )
else:
   print ("Line 3 - a is not less than b")

if ( a > b ):
   print ("Line 4 - a is greater than b")
else:
   print ("Line 4 - a is not greater than b")

a,b = b,a #values of a and b swapped. a becomes 10, b becomes 21

if ( a <= b ):
   print ("Line 5 - a is either less than or equal to  b")
else:
   print ("Line 5 - a is neither less than nor equal to  b")

if ( b >= a ):
   print ("Line 6 - b is either greater than  or equal to b")
else:
   print ("Line 6 - b is neither greater than  nor equal to b")

输出

当您执行上述程序时，它会产生以下结果 −

Line 1 - a is not equal to b
Line 2 - a is not equal to b
Line 3 - a is not less than b
Line 4 - a is greater than b
Line 5 - a is either less than or equal to  b
Line 6 - b is either greater than  or equal to b