Python逻辑运算符示例
下表列出了所有Python语言支持的逻辑运算符。假设变量a持有10和变量b持有20,则:
运算符 | 描述 | 例子 |
---|---|---|
and | 所谓逻辑与运算符。如果两个操作数都为真,则条件为真。 | (a and b) 为 true. |
or | 所谓逻辑OR运算符。如果有两个操作数都为非零,则条件变为真。 | (a or b) 为 true. |
not | 所谓逻辑非运算符。用反转操作数的逻辑状态。如果条件为true,则逻辑非运算符将为false。 | not(a and b) 为 false. |
示例:
试试下面的例子就明白了所有的Python编程语言提供了逻辑运算符:
#!/usr/bin/python a = 10 b = 20 c = 0 if ( a and b ): print "Line 1 - a and b are true" else: print "Line 1 - Either a is not true or b is not true" if ( a or b ): print "Line 2 - Either a is true or b is true or both are true" else: print "Line 2 - Neither a is true nor b is true" a = 0 if ( a and b ): print "Line 3 - a and b are true" else: print "Line 3 - Either a is not true or b is not true" if ( a or b ): print "Line 4 - Either a is true or b is true or both are true" else: print "Line 4 - Neither a is true nor b is true" if not( a and b ): print "Line 5 - Either a is not true or b is not true" else: print "Line 5 - a and b are true"
当执行上面的程序它会产生以下结果:
Line 1 - a and b are true Line 2 - Either a is true or b is true or both are true Line 3 - Either a is not true or b is not true Line 4 - Either a is true or b is true or both are true Line 5 - Either a is not true or b is not true