python之函数用法round()

# -*- coding: utf-8 -*-

#python 27

#xiaodeng

#python之函数用法round()

#http://www.cnblogs.com/hongfei/p/3858256.html

#round()

#说明：返回有N个小数点浮点数，

'''

round(...)

    round(number[, ndigits]) -> floating point number

    Round a number to a given precision in decimal digits (default 0 digits).

    This always returns a floating point number.  Precision may be negative.

'''

#案例

print round(3.1415926,3)#3.142

print round(3.1415926,2)#3.14

print round(3.1415926,10)#3.143.1415926

print round(100.000056, 3)#100.0

print round(-100.000056, 3)#-100.0