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Date: Tue, 19 Feb 2013 09:09:16 +0000
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 <CABvT1DFtvhBL7pbveHPK_b-cVsA++ria=MZBdw_GkjA4oMz2jQ@mail.gmail.com>
Subject: Re: Fixed precision of floating point number not respected in views
From: Robert Newson <rnewson@apache.org>
To: "user@couchdb.apache.org" <user@couchdb.apache.org>
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"I have stored fixed precision numbers in a database". You haven't,
unfortunately, because you can't. Javascript only has one kind of
number, 64-bit floating point.


If you want fixed precision, you'll need to store your numbers in
strings and manipulate them that way too. A quick google in the past
has shown a few "bignum" libraries for Javascript.

B.

On 19 February 2013 08:20, Luca Morandini <lmorandini@ieee.org> wrote:
> On 02/19/2013 07:05 PM, Luca Morandini wrote:
>>
>> Folks,
>>
>> I have stored fixed precision numbers in a database, but when they are
>> spit out by
>> a view, the precision is full, and -which is worse- the trailing decimal
>> digits
>> are not all zeroes.
>
>
> In the CouchDB: The Definitive Guide", I have found out that "most clients"
> would interpret, say, 15.7 as 15.69999999999 (or so), which I suppose is
> exactly what I observed... but what is meant as "client" in this context, a
> view engine ?
>
> Anyway, any view to tune this feature of the JavaScript view engine ?
>
>
> Regards,
>
> Luca Morandini
> Data Architect - AURIN project
> Department of Computing and Information Systems
> University of Melbourne
> Tel. +61 03 903 58 380
> Skype: lmorandini
>