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这些运算符比较它们两侧的值并确定它们之间的关系。 它们也称为关系运算符。

假设变量a保持10，变量b保持20，则 -

操作者	描述	例
==	如果两个操作数的值相等，则条件成立。	（a == b）不是真的。
!=	如果两个操作数的值不相等，则条件成立。	（a！= b）是真的。
<>	如果两个操作数的值不相等，则条件成立。	（a <> b）是真的。 这类似于！=运算符。
>	如果左操作数的值大于右操作数的值，则条件变为真。	（a> b）不是真的。
<	如果左操作数的值小于右操作数的值，则条件变为真。	（a
>=	如果左操作数的值大于或等于右操作数的值，则condition变为true。	（a> = b）不是真的。
<=	如果左操作数的值小于或等于右操作数的值，则条件变为真。	（a <= b）是真的。

例子 (Example)

假设变量a保持10，变量b保持20，则 -

#!/usr/bin/python
a = 21
b = 10
c = 0
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 not equal to b"
else:
   print "Line 3 - a is equal to b"
if ( a < b ):
   print "Line 4 - a is less than b" 
else:
   print "Line 4 - a is not less than b"
if ( a > b ):
   print "Line 5 - a is greater than b"
else:
   print "Line 5 - a is not greater than b"
a = 5;
b = 20;
if ( a <= b ):
   print "Line 6 - a is either less than or equal to  b"
else:
   print "Line 6 - a is neither less than nor equal to  b"
if ( b >= a ):
   print "Line 7 - b is either greater than  or equal to b"
else:
   print "Line 7 - b is neither greater than  nor equal to b"

执行上述程序时，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 equal to b
Line 4 - a is not less than b
Line 5 - a is greater than b
Line 6 - a is either less than or equal to b
Line 7 - b is either greater than or equal to b