实例说明Python中比较运算符的使用

下表列出了所有Python语言支持的比较操作符。假设变量a持有10和变量b持有20，则：

例如：

试试下面的例子就明白了所有的Python编程语言提供的比较操作符：

    #!/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"

当执行上面的程序它会产生以下结果：

    Line 1 - a is not equal to b
    Line 2 - a is not equal to b
    Line 3 - a is not 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