Format operator (%)

String formatting symbols

Format Character Conversion mode

%c converted to character (ASCII value, or string of length one )

%r takes precedence over string conversions with the repr () function

%s takes precedence over string conversion with the str () function

%d/%i turns into signed decimal number

%u turns into unsigned decimal number

%o Turn unsigned octal number

%x/%x (Unsigned) turns to unsigned hexadecimal number (x/x represents the case of converted 16 characters )

%e/%e turns into scientific notation (e/e control output e/e)

%f/%f into floating-point numbers ( Fractional parts are naturally truncated )

shorthand for %g/%g%e and %f/%e and %f

Before the decimal point is less than 6 bits, the floating point type, a total of six digits, before the decimal point is larger than 6 bits, then the scientific notation, also a total of six bits

% output %

Formatting operator Auxiliary directives

Symbolic effect

* Define width or decimal point accuracy

-Used for left alignment

+ Show plus sign (+) in front of positive number

<sp> show spaces in front of positive numbers

# 0 (' 0 ')is displayed in front of the octal number, preceded by ' 0x ' or ' 0X 'in hexadecimal ( depending on ' x ' or ' X ')

0 The number shown is preceded by ' 0 ' instead of the default space

% ' percent ' output a single '% '

(VAR) mapping variable ( dictionary parameter )

M.N m is the smallest total width displayed , and N is the number of digits after the decimal point ( if available )

Here are some examples of using format Strings :

Hex Output :

>>> "%x"% 108

' 6c '

>>>

>>> "%x"% 108

' 6C '

>>>

>>> "% #X"% 108

' 0x6c '

>>>

>>> "% #x"% 108

' 0x6c '

Floating-point number and scientific notation output :

>>>

>>> '%f '% 1234.567890

' 1234.567890 '

>>>

>>> '%.2f '% 1234.567890

' 1234.57 '

>>>

>>> '%E '% 1234.567890

' 1.234568E+03 '

>>>

>>> '%e '% 1234.567890

' 1.234568e+03 '

>>>

>>> '%g '% 1234.567890

' 1234.57 '

>>>

>>> '%G '% 1234.567890

' 1234.57 '

>>>%.7g '% 1234.567890

' 1234.568 '

>>> '%g '% 123456.7890

' 123457 '

>>> "%e"% (1111111111111111111111L)

' 1.111111e+21 '

Integer and string output :

>>> "%+d"% 4

' +4 '

>>>

>>> "%+d"%-4

'-4 '

>>>

>>> "We are at%d%%"% 100

' We is at 100% '

>>>

>>> ' Your host is:%s '% ' Earth '

' Your host Is:earth '

>>>

>>> ' Host:%s\tport:%d '% (' Mars ', 80)

' Host:mars port:80 '

>>>

>>> num = 123

>>> ' Dec:%d/oct:% #o/hex:% #X '% (num, num, num)

' dec:123/oct:0173/hex:0x7b '

>>>

>>> "mm/dd/yy =%02d/%02d/%d"% (2, 15, 67)

' Mm/dd/yy = 02/15/67 '

>>>

>>> W, p = ' Web ', ' page '

>>> ' http://xxx.yyy.zzz/%s/%s.html '% (W, p)

' Http://xxx.yyy.zzz/Web/page.html '

The parameters of the dictionary type are provided to the format operator .

>>> ' There is% (Howmany) d% (Lang) s quotation Symbols '% {' lang ': ' Python ', ' Howmany ': 3}

' There is 3 Python quotation Symbols '

Format operator (%)