file types

[Bill Brown]

Rob,

I'm not sure what you mean by a type 3 file, but if you're
looking at the "format:" line in the cellhd file, this 
number is the (number_of_bytes - 1) which is required to
store the largest number in the file, ranging from 0 to 3 
(1-4 bytes).  If you're trying to get it into "format: 1"
then your range has to be 0-65536 - I'm not sure how
negative numbers are treated, but from a couple of trials,
it looks to me like any data that contains negatives are
always format 3, for some reason.  So you might have to 
do some creative "r.mapcalc" to rescale your data into a
2-byte range, then rescale it after importing.

Also, before you try importing it you may need to 
uncompress the data (r.compress -u data_layer).

- Bill
brown at gis.uiuc.edu