How to round up/down integer number?

[peachdot]

hi,

i want my 2.25x10^12 to be rounded to 2x10^12 and 2.75x10^12 to 3x10^12.

How can i do that?

thanx

[dwblas]

You probably have to roll your own function, i.e. convert to string, parse from right to left and split on the first non zero number, round as desired and append/multiply by the right-most number of zeros.

[dwblas]

You probably have to roll your own function, i.e. convert to string, parse from right to left and split on the first non zero number, round as desired and append/multiply by the right-most number of zeros. Unless you always know how many zeros come after the digits.

[bvdet]

Following is a function I use in my work for rounding off to a predetermined increment:

>>> def round_length_near(length, increment=.0625):
...     if not increment:
...         return length
...     return round(length/float(increment)) * increment
... 
>>> round_length_near(22500000000, 10000000000)
20000000000.0
>>> round_length_near(27500000000, 10000000000)
30000000000.0

It requires converting the string to int or float.

>>> "%e" % 22500000000
'2.250000e+010'
>>> float('2.250000e+010')
22500000000.0
>>>