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From: Chris Torek <nospam@torek.net>
Newsgroups: comp.lang.python
Subject: Re: Significant figures calculation
Date: 25 Jun 2011 19:04:52 GMT
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In article <mailman.386.1308949143.1164.python-list@python.org>
Jerry Hill  <malaclypse2@gmail.com> wrote:
>I'm curious.  Is there a way to get the number of significant digits
>for a particular Decimal instance?

Yes:

def sigdig(x):
    "return the number of significant digits in x"
    return len(x.as_tuple()[1])

import decimal
D = decimal.Decimal

for x in (
    '1',
    '1.00',
    '1.23400e-8',
    '0.003'
):
    print 'sigdig(%s): %d' % (x, sigdig(D(x)))
-- 
In-Real-Life: Chris Torek, Wind River Systems
Intel require I note that my opinions are not those of WRS or Intel
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