GMT

Basically I hacked example 33 (which is a perfect template for some Machine Learning i'm doing on seafloor age; thanks very much .

The upshot is that for for a transect along the MAR (-28 45.375, -29 43.36) i want to stack the values grdtrack pulls out of a good sized area.

gmt grdtrack ridge.txt -Gspac.nc -C2300k/4k/10k -Sm+sstack.txt -V > table.txt

grdtrack: Processing input grid(s)
grdtrack: Sampled 14425 points from grid spac.nc (321 x 151)

if I increase the stack "width" width from 2380 km to 2400 km , it hangs. At first I thought it was some sort of 32k roll over as the number of points was getting close to 32k, but I reduced the number of samples along the stack from every 2k to every 4k, and it still hangs.

Seems unlikely that there is a limit to 2400km, but I notice the seafloor age grid I downloaded from U Sydney, happens to have a NaN, at the western edge of stack. See attachment.

So I think grdtrack hangs if using a "stack" and the grid has a NaN in the stack area. Or something. Coplete code below, but basically example 33

-jj

p.s. I left the the CLUT "wrong", i.e. b&w to make it easier to see the "stack", as I am color blind...

sherwood:Age jbecker$ bash -x gmtExample33.sh
+ ps=example_33.ps
+ rm -f example_33.ps gmt.conf z.cpt spac_int.nc ridge.txt table.txt env.txt stack.txt
+ gmt grdcut age.3.6.nc -R45W/13W/35N/50N -fg -Gspac.nc
+ gmt makecpt -Crainbow -T-5000/-2000/500 -Z
+ gmt grdgradient spac.nc -A15 -Ne0.75 -Gspac_int.nc
+ gmt grdimage spac.nc -Ispac_int.nc -Cz.cpt -JM6i -P -Baf -K -Xc --FORMAT_GEO_MAP=dddF
+ cat
+ gmt psxy -Rspac.nc -J -O -K -W2p,red ridge.txt
+ gmt psxy -R -J -O -K -Sc.11i -Gred ridge.txt
+ gmt grdtrack ridge.txt -Gspac.nc -C2300k/4k/10k -Sm+sstack.txt -V

—> Hangs here if if use -C2400k/4k/10k

grdtrack: Processing input grid(s)
grdtrack: Sampled 14425 points from grid spac.nc (321 x 151)
+ gmt psxy -R -J -O -K -W0.5p table.txt
+ gmt gmtconvert stack.txt -o0,5
+ gmt gmtconvert stack.txt -o0,6 -I -T
+ gmt psxy -R-1400/1400/0/20000 '-Bxafg1000+lDistance from ridge (km)' '-Byaf+lAge (ky)' -BWSne -JX6i/3i -O -K -Glightgray env.txt -Y6.5i
+ gmt psxy -R -J -O -K -W3p stack.txt
+ echo '0 -2000 MEDIAN STACKED PROFILE'
+ gmt pstext -R -J -O -K -Gwhite -F+jTC+f14p -Dj0.1i
+ gmt psxy -R -J -O -T
sherwood:Age jbecker$