[GRASS5] Severe internal bugs in raster format

[Markus Neteler]

Dear developers,

sorry for bad news: but it seems there is a lot
of confusion in raster format read/write in several
modules:

Example:
 d.rast a_raster_map
 d.rast.zoom # we want to look at some pixels only
 d.rast.num  # show cell values
 d.what.rast # query with mouse: result is different
 r.out.ascii # result is different as well

(from A. Lobo:)
r.stats: some inconsistent results comparing to r.average
 *First, I compute the per-class averages:
     r.average base=medv cover=test out=borra.me
 *Second, I check the result for, i.e., class 23:
     d.what.rast map=medv,borra.me
     2676500(E) 4409500(N)
           medv in user1  (23)S_SUPRAMEDITERRANEAN_ZONE
           borra.me in user1, quant   (111)
           borra.me in user1, actual  (110.794075)
 *Third, I compute the statistics for each class, but the results are not
  the same as given by d.what.rast. For example, for class 23:
     r.stats -c in=medv,borra.me
     r.stats:  100%
       ...
       23 110.299171-110.744906 6082
       ...
 *While d.what.rast was giving 110.794075.

We should check this quickly, otherwise we cannot trust any result.
I guess the problem is due to ".5" (half raster cell) addition
for query any some potential mixture of 
  - save values at cell center
  - save values at cell corner (which is wrong as far as I know but correct
                                for ESRI).


Another bug: r.in.arc reads in ARC/INFO grid files reversed.
ESRI saves from lower left to upper right, GRASS from
upper left to lower right. The module does not (yet) take
care of this. I would be able to fix in GRASS 4.x but in GRASS 5
the row number cannot be specified any more (G_put_raster_c_row()).
So we have to flip the input file or something else... How to do this?

Your help is appreciated!
Hope to have better news soon,

 Markus

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