Re: precision Issues?

Hi Jeff,

I think it's a rounding error from going back and forth between
lat/lons, pixels, and back to lat/lons. Since pixels are actually a
specific size in lat/lon space, the precision is not absolute when you
go back and forth.

- Don

On Thursday, April 11, 2002, at 10:47 PM, Jeff Kirby wrote:

> Hi again :-)
>
> I give openmap a center co-ord (lat and lon ) and a scale ( got via
> ProjMath ) and the center i get back is not the same... is out a
> little...
>
> using proj.getUpperLeft() and proj.getLowerRight() methods.. this is my
> situation
>
> ask for centre -157.23015 lon 21.38713 lat
> and get centre -157.23013 lon 21.387129 lat
>
> obviously different requests gather different levels of errors... im
> wondering whats causing this. My math is all Float, and seems good to
> me ... perhaps its what OM depends on in calculating its bits? or a
> deg-rad problem?...
>
> Jeff
>
>
>
>
>
>
> --
> Jeff Kirby, jeff@consunet.com.au on 12/04/2002
>
> --
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>

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Don Dietrick, BBN Technologies, dietrick@bbn.com
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