[Sharon Mesick x7665]

Nicola Fohrer wrote:
> 
> Dear Grass Users,
> 
> importing Ascii-File to Erdas Gis - exporting as Grass -File
> 
> I have created a map (DEM) in Erdas by reading an ASCII-File. The
> data type is Float Single and the projection is Transverse Mercator.
> Exporting this map as a Grass-file, Erdas gives the warning that
> float data can only be exported as integer.
> If I accept and create a location and mapset it can only be imported
> into Grass without any projection (plane) although it is exported as
> Transverse Mercator.
> 1. Is Grass not able to manage float data maps ?
> 2. How can I save the projection TM during the transfer from Erdas to
>     Grass ?
> 
> Stephan
> 
> ********************************
> Dr. sc. agr. Nicola Fohrer
> Wissenschaftliche Assistentin
> Institut fuer Landeskultur
> Senckenbergstr. 3
> 35 390 Giessen
> Tel:0641/99 37385
> Fax:0641/99 37389
> email:Nicola.Fohrer at agrar.uni-giessen.de

My experience with GRASS is somewhat limited, but I can tell you for
certain that a GRASS raster file can only be an integer type.  For my
data sets, where the float value is very important, I pre-process the
ASCII data by mulitplying such that the floating point becomes an
integer which contains all necessary values.  For example, 25.9 bcomes
259 - I also have to adjust my standardized color scale (in the colr
directory) and my category file to accomodate this change.  Hope this
info will be useful to you.

Sharon Mesick
mesick at dolphins.ssc.nasa.gov