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符。
假設變數 a = 10，變數b = 20，那麼-
| 操作符 | 描述 | 示例 |
|---|---|---|
| == |
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 != 運算符 |
| > |
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. |
示例
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
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Python3變數類型
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Python3基本運算符