Python3比較運算子範例

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。它們也被稱為關係運算子。

假設變數 a = 10，變數b = 20，那麼-

操作符	描述	範例
==	如果兩個運算元的值相等，則條件變為真	(a == b) 不為 true.
!=	如果兩個運算元的值不相等，則條件變為真
<>	如果兩個運算元的值不相等，則條件變為真	(a <> b) 為 true. 這類似於 != 運算子
>	如果左運算元的值大於右運算元的值，則條件為真	(a > b) 不為true.
<	如果左運算元的值小於右運算元的值，則條件為真。	(a < b) 為 true.
>=	如果左運算元的值大於或等於右運算元的值，則條件為真	(a >= b) 不為 true.
<=	如果左運算元的值小於或等於右運算元的值，則條件為真	(a <= b) 為 true.

範例

假設變數 a = 10，變數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")

當你執行上面的程式它產生以下結果 -

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