Python元組
元組是另一個數據類型，類似于List（列表）。
元組用"()"標識。內部元素用逗號隔開。但是元素不能二次賦值，相當于只讀列表。
#!/usr/bin/python# -*- coding: UTF-8 -*-tuple = ( 'abcd', 786 , 2.23, 'john', 70.2 )tinytuple = (123, 'john')print tuple # 輸出完整元組print tuple[0] # 輸出元組的第一個元素print tuple[1:3] # 輸出第二個至第三個的元素 print tuple[2:] # 輸出從第三個開始至列表末尾的所有元素print tinytuple * 2 # 輸出元組兩次print tuple + tinytuple # 打印組合的元組
以上實例輸出結果：
('abcd', 786, 2.23, 'john', 70.2)abcd(786, 2.23)(2.23, 'john', 70.2)(123, 'john', 123, 'john')('abcd', 786, 2.23, 'john', 70.2, 123, 'john')以下是元組無效的，因為元組是不允許更新的。而列表是允許更新的：
#!/usr/bin/python# -*- coding: UTF-8 -*-tuple = ( 'abcd', 786 , 2.23, 'john', 70.2 )list = [ 'abcd', 786 , 2.23, 'john', 70.2 ]tuple[2] = 1000 # 元組中是非法應用list[2] = 1000 # 列表中是合法應用
Python邏輯運算符
Python語言支持邏輯運算符，以下假設變量a為10，變量b為20：
以下實例演示了Python所有邏輯運算符的操作：
#!/usr/bin/pythona = 10b = 20c = 0if ( 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 = 0if ( 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 or both are not true"else: print "Line 5 - a and b are true"
以上實例輸出結果：
Line 1 - a and b are trueLine 2 - Either a is true or b is true or both are trueLine 3 - Either a is not true or b is not trueLine 4 - Either a is true or b is true or both are trueLine 5 - Either a is not true or b is not true or both are not true
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