python：格式化输出整数

import math
#default
print "PI = %f" % math.pi
#width = 10,precise = 3,align = left
print "PI = %10.3f" % math.pi
#width = 10,precise = 3,align = rigth
print "PI = %-10.3f" % math.pi
#前面填充字符
print "PI = %06d" % int(math.pi)
 
#输出结果
#PI = 3.141593
#PI =      3.142
#PI = 3.142
#PI = 000003
#浮点数的格式化，精度、度和