floating point | null data in GRASS!

Darrell McCauley mccauley at ecn.purdue.edu
Fri Mar 12 17:07:13 EST 1993

Bill Hargrove (hnw at mtqgrass.ESD.ORNL.GOV) writes on 12 Mar 93:

>     I don't really see the big deal about floating point maps and zero vs
>no data problems.  Multiply by 10 times the number of decimals of accuracy
>you need to take care of the first problem.  Shift all category values up
>one notch to take care of the other.

What if you have one cell value that is 1e6 and another that is 1e-6?
If you have no values in between those, not all grass tools act
so nice (like r.reclass).

You also have to document very well what you have done - so that someone
using r.what on your maps later on will not be confused.

>     IMHO, a much more severe limitation to the current implementations of
>GRASS is the current XDRIVER.  The named fifo pipe technique is a kludge at
>best.  GRASS needs *real* X-window support, including more than 8 plane

I agree that this is also a problem also. Perhaps we should
discuss funding sources AND programming issues.


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