[GRASS-user] Grass/GMT problem

[Roger Mason]

"Brent Wood" <b.wood at niwa.co.nz> writes:

> As a first check, with GMT, try grdinfo to make sure the values seem sensible. You may be able to try grdedit if you have installed it to see the Z values of the grid in a spreadsheet layout to check the grid file, although I'm not sure if it handles non-standard grid files.
>
> Being more a GMT than GRASS user, I'd also look at exporting the XYZ ascii data from GRASS & then grid them with xyz2grd or surface in GMT for contouring :-) Or contour in GRASS, & export the contours for use with GMT (ogr2ogr supports GMT multiline files now). 
>
> Not a fix, but possible alternative approaches.
>

Thanks for the suggestions.  I had tried dumping the data as xyz ascii
data just to see what they looked like but did not know of xyz2grd.
I did eventually stumble on ncdump so was able to look at the data as
ascii.  My initial approach was to use r.surf.fractal and do the
contouring in GRASS, I changed to contouring in GMT because the GRASS
contours were solid lines and I wanted dashed lines (how petty and
trivial one can be!) with labels.  If I do the contouring in GRASS and
export for use with GMT can I modify their appearance and add labels?

What I'm doing here is to generate fake landscapes that will be used
to train geology students in solving simple outcrop problems given
information about the strike, dip and vertical thickness of units,
along with one or more known outcrop points.  The idea is to be able
to generate such maps quickly so the students can get lots of practice
without me having to go through the labour of map preparation by hand.

At the moment I have a method that is working tolerably well but I
will try out any and all alternative suggestions.

Thanks to all,

Roger