String Format Operator Directives

When using the string format operator (see Table B.5), you may enhance or fine-tune the object display with the directives shown in

Table B.5. String Format Operator Conversion Symbols

Format Symbol	Conversion
%c	Character (integer [ASCII value] or string of length 1)
%r[a]	String conversion via repr() prior to formatting
%s	String conversion via str() prior to formatting
%d / %i	Signed decimal integer
%u[b]	Unsigned decimal integer
%o[b]	(Unsigned) octal integer
%x[b] / %X[b]	(Unsigned) hexadecimal integer (lower/UPPERcase letters)
%e / %E	Exponential notation (with lowercase 'e'/UPPERcase 'E')
%f / %F	Floating point real number (fraction truncates naturally)
%g / %G	The shorter of %e and %f/%E% and %F%
%%	Percent character ( % ) unescaped

^[a] New in Python 2.0; likely unique only to Python.

^[b] %u/%o/%x/%X of negative int will return a signed string in Python 2.4+.

Table B.6. Format Operator Auxiliary Directives

Symbol	Functionality
*	Argument specifies width or precision
-	Use left justification
+	Use a plus sign ( + ) for positive numbers
<sp>	Use space-padding for positive numbers
#	Add the octal leading zero ('0') or hexadecimal leading '0x'
	or '0X', depending on whether 'x' or 'X' were used
0	Use zero-padding (instead of spaces) when formatting numbers
%	'%%' leaves you with a single literal '%'
(var)	Mapping variable (dictionary arguments)
m.n	m is the minimum total width and n is the number of digits to display after the decimal point (if applicable)