Python3比較運算符實例

這些操作符對它們的兩側的值進行比較，並決定它們之間的關係。它們也被稱爲關係運算符。

假設變量 a = 10，變量b = 20，那麼-

操作符

描述

示例

==

如果兩個操作數的值相等，則條件變爲真

(a == b) 不爲 true.

!=

如果兩個操作數的值不相等，則條件變爲真

<>

如果兩個操作數的值不相等，則條件變爲真

(a <> b) 爲 true. 這類似於 != 運算符

>

如果左操作數的值大於右操作數的值，則條件爲真

(a > b) 不爲true.

<

如果左操作數的值小於右操作數的值，則條件爲真。

(a < b) 爲 true.

>=

如果左操作數的值大於或等於右操作數的值，則條件爲真

(a >= b) 不爲 true.

<=

如果左操作數的值小於或等於右操作數的值，則條件爲真

(a <= b) 爲 true.

示例

假設變量 a = 10，變量b = 20，那麼 -

#!/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")

當你執行上面的程序它產生以下結果 -

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