Width and Precision : Format « String « Python Tutorial

from math import pi 

print '%10f' % pi # Field width 10 

print '%10.2f' % pi # Field width 10, precision 2 

print '%.2f' % pi # Precision 2 

print '%.5s' % 'Guido van Rossum' 

use an * as the width or precision (or both), in which case the number will be read from the tuple argument

print '%.*s' % (5, 'Guido van Rossum')

5.10.Format
	5.10.1.	String formatting is done with the string formatting operator, the percent (%) sign.
	5.10.2.	Formatted String
	5.10.3.	String format
	5.10.4.	A basic conversion specifier
	5.10.5.	use the string format operator ( % ), or put all of the substrings in a list, and using one join() call to put them all together
	5.10.6.	The syntax for using the format operator is as follows: format_string % (arguments_to_convert)
	5.10.7.	Format Operator Auxiliary Directives
	5.10.8.	String Formatting Conversion Types
	5.10.9.	print paired with the string format operator ( % )
	5.10.10.	Width and Precision
	5.10.11.	Signs, Alignment, and Zero-Padding
	5.10.12.	A minus sign (-) left-aligns the value:
	5.10.13.	A blank (" ") means that a blank should be put in front of positive numbers
	5.10.14.	a plus (+) means that a sign should precede both positive and negative numbers
	5.10.15.	String formatting.
	5.10.16.	String-formatting codes
	5.10.17.	%[(name)][flags][width][.precision]code
	5.10.18.	The %e, %f, and %g formats display floating-point numbers in different ways, as the following interaction demonstrates:
	5.10.19.	Dictionary-Based String Formatting