Format specifiers: a quick reference
Format specifiers: a quick reference
Format specifiers actually constitute a “mini-language” of their own. For a complete reference, see the section entitled “Format Specification Mini-Language” in the Python documentation for strings (https://docs.python.org/3/library/string.html).
Remember that format specifiers are optionally included in f-string replacement fields. The format specifier is separated from the replacement expression by a colon. Examples:
>>> x = 0.16251`
>>> f'{x:.1%}'
'16.3%'
>>> f'{x:.2f}'
'0.16'
>>> f'{x:>12}'
' 0.16251'
>>> f'{x:.3E}'
'1.625E-01'Here’s a quick reference for some commonly used format specifiers:
| option | meaning | example |
|---|---|---|
< |
align left, can be combined with width | <12 |
> |
align right, can be combined with width | >15 |
f |
fixed point notation, combined with precision | .2f |
% |
percentage (multiplies by 100 automatically) | .1% |
, |
use thousands separators, for example, 1,000 | , |
E |
scientific notation, combined with precision | .4E |
Original author: Clayton Cafiero < [given name] DOT [surname] AT uvm DOT edu >
No generative AI was used in producing this material. This was written the old-fashioned way.
This material is for free use under either the GNU Free Documentation License or the Creative Commons Attribution-ShareAlike 3.0 United States License (take your pick).