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Re: 19990408: storing and retrieving exact floating-point value

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  • Subject: Re: 19990408: storing and retrieving exact floating-point value
  • Date: Thu, 08 Apr 1999 14:55:28 -0600
Hi Harry,

> cc: "Harry L Jenter, Hydrologist, Reston, VA "<address@hidden>,
> cc: "Michael P Duff, Student Intern, Reston, VA "<address@hidden>
> From: Harry Jenter <address@hidden>
> Subject: inserting 1e35 with netCDF-perl
> Organization: U.S.G.S.
> Keywords: 199904082039.OAA25794 netCDF Perl

In the above message, you wrote:

> I've been using netCDF-perl for awhile now and am extremely happy
> with it. However, I am having trouble with something.  I've been
> writing an application that is intended to adhere strictly to
> NOAA's EPIC convention.  In this convention, the value for
> missing data is supposed to be 1e35.  When i use netCDF-perl to
> write 1e35 into an array and then I read it, I get a value that
> will not cause the perl statement ($value == 1e35) to be true. 
> If I print $value, I get something like $value =
> 1.00000012390876e35.  Is there a way to force netCDF-perl to
> write 1e35 EXACTLY?  I'm stumped. Thanks for any help you can
> provide.

Interesting.  The problem solution isn't immediately apparent to me.

What's the type of the netCDF variable that's getting the 1e35 value?

--------
Steve Emmerson   <http://www.unidata.ucar.edu>