[GRASS-user] importing GMT grids

[Carlos "Guâno" Grohmann]

any good advice on importing GMT grids? r.in.bin keeps complaining
about the file size, no matter what byte size I choose, and setting it
to get the header from the grid, makes it error on "east must be
larger than west". Exporting the grid to xyz (grd2xyz) and then
importing with r.in.xyz seems to work, but the resulting image is full
of artifacts (see attach). I tried to change the grid registration in
GMT (grdedit), and the boundaries too (in surface), giving it a
half-pixel difference, but all came in the same way.

If anyone wants to try, this is the xyz file:
http://www.igc.usp.br/pessoais/guano/temp/3arcsec.csv

and these are the commands I used:

nearneighbor 3arcsec.csv -R337575/351435/3855915/3872175 -I30/30 -S200
-V -Goutnear.grd
grdedit outnear.grd -T
grdinfo outnear.grd
grd2xyz outnear.grd --D_FORMAT=%f >near.xyz

and

surface 3arcsec.csv -R337575/351435/3855915/3872175 -I30/30 -T0.35 -V -Gout.grd

grdedit out.grd -T
grdinfo out.grd
grd2xyz out.grd --D_FORMAT=%f >spline.xyz


the commands above have the "half pixel displacement" I mentioned, for
this region:

projection: 1 (UTM)
zone:       11
datum:      wgs84
ellipsoid:  wgs84
north:      3872190
south:      3855900
west:       337560
east:       351450
nsres:      30
ewres:      30
rows:       543
cols:       463
cells:      251409


thanks

Carlos

-- 
+-----------------------------------------------------------+
              Carlos Henrique Grohmann - Guano
  Visiting Researcher at Kingston University London - UK
  Geologist M.Sc  - Doctorate Student at IGc-USP - Brazil
Linux User #89721  - carlos dot grohmann at gmail dot com
+-----------------------------------------------------------+
_________________
"Good morning, doctors. I have taken the liberty of removing Windows
95 from my hard drive."
--The winning entry in a "What were HAL's first words" contest judged
by 2001: A SPACE ODYSSEY creator Arthur C. Clarke

Can't stop the signal.
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