1. '%'字符串格式化html
#方法一: '%' num = 10 print('--the number is %d--'%num) #output: "--the number is 10--" print('the float number is %f'%-3.14) #output: "the float number is -3.140000",自動格式 print('the float number is %6.3f'%-3.14) #output: "the float number is -3.140" #此時6.3的6表示寬度(包括正負號和小數點),3表示精度(也就是小數點位數,浮點型時) print('the float number is %-9.3d'%-3) #output: "the float number is -003 " #此時-9.3d,d表示整型,此時3表示顯示的數字寬度,不足的補零,9表示整個字符寬度,不足的補空格 print('the float number is %09.3f'%-3.14) #output: "the float number is -0003.140" #浮點型,此時09.3表示精度爲3位,寬度爲9,不足的在前面補零 print('the float number is %-9.3f'%-3.14) #output: "the float number is -3.140 " #此時-9.3表示精度爲3位,寬度爲9,不足的在後面補空格(由於沒有指定補零),最前面的負號'-'表示左對齊
2. format字符串格式化python
#方法二: format print("what is your {}: {}!".format('name','Jack')) # output: "what is your name: Jack!" #依次對應前面的括號,當括號內沒有值時 print('what is your {flag}?--- {1},and {0}? ---{myname}'.format(flag='name','you','Bob',myname='Lily')) # SyntaxError: positional argument follows keyword argument,遵照python的參數賦值順序,關鍵字參數應該在後面 print('what is your {flag}?--- {1},and {0}? ---{myname}'.format('you','Bob',flag='name',myname='Lily')) #output: "what is your name?--- Bob,and you? ---Lily",遵照python賦值順序 print('what is your {flag}?--- {1},and {0}? ---{myname}'.format('you','Bob','name','Lily')) # KeyError: 'flag',由於前面的格式寫了'flag',可是後面沒有找到 print('what is your {2}?--- {1},and {0}? ---{3}'.format('you','Bob','name','Lily')) #output: "what is your name?--- Bob,and you? ---Lily",以format中元組的索引賦值 print('what is your {1[0]}--- {0[1]},and {0[0]} ---{1[1]}'.format(('you','Bob'),('name','Lily'))) #output: "what is your name--- Bob,and you ---Lily",元組嵌套元組的索引賦值
3. format帶精度,對齊,補足位spa
## ^、<、>分別是居中對齊、左對齊、右對齊 print('{0}+{1}={2:$>6}'.format(2.4,3.1,5.5)) #"2.4+3.1=$$$5.5",>表示右對齊,6位寬度,$用於補足空位 print('{0}+{1}={2:$^6}'.format(2.4,3.1,5.5)) #"2.4+3.1=$5.5$$",^表示居中對齊 print('{0}+{1}={2:$<6}'.format(2.4,3.1,5.5)) #"2.4+3.1=5.5$$$",<表示左對齊 print('{0}+{1}={2:$<6.2f}'.format(2.4,3.1,5.5)) #"2.4+3.1=5.50$$",6.2f表示寬6位,精度是2位,浮點型 print('{0:$<6.2f}'.format(5.5)) #或者 print('{:$<6.2f}'.format(5.5)) #"5.50$$",只有一個參數時
4. format的字典傳遞關鍵字參數格式化、列表傳遞位置參數格式化3d
dict_para = {'flag':'question','name':'Jack'} print("what is your {flag}: {name}!".format(**dict_para)) #"what is your question: Jack!",用字典傳遞參數,'**'用於收集關鍵字參數 list_para = ['question','Jack'] print("what is your {}: {}!".format(*list_para)) # "what is your question: Jack!",用列表傳遞參數,'*'用於收集參數
參考:code