[Gdal-dev] floating point bug

[Maciek Sieczka]

Frank,

> I find it hard to believe that GDAL's AIG driver would misreport a
> floating point Arc/Info Binary Grid as Int16.  If you can provide a sample
> Arc/Info grid that demonstrates this problem I will investigate.

I digged a little more and I'm confused.

I noticed that whether GDAL recognises the an FP ARCGrid as FP or INT
depends somehow on the proportion and distribution of null/data
cells in a file but I can't find a simple rule for this (and I may be wrong
as well). Anyway if the FP grid file is "100% data" it is always recognised
as FP. But if it contains nulls then GDAL will see it as INT or FP
dependending on the file itself. Examples for both cases taken out from my
FP ARCGrid file are attached in the arc.tgz. If you need a bigger one please
let me know.

> GDAL does not support floating point ESRI bil files.  I don't know what
> they put in the .hdr file to indicate floating point.  So the file is
> misused as integer and all the values are crazy.  Can you provide the
> .hdr file so can see if there are any clues it is floating point?

I read the problem's solved but just in case included are the world and
header files of my FP dem.bil.

Cheers
Maciek
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