Surface map plot

Q&A
1

Hello everyone. Please I need an assistance, I try to plot surface map with an amplitude but is not working, only the map shows but other gave me errors. please help out. Below is the code and the data
#!/bin/bash

gmt begin South_Africa pdf

 gmt set MAP_FRAME_TYPE plain
 gmt set FONT_LABEL 16p
 gmt makecpt -Cjet -T-15/30/2

gmt pscoast -R16/33/-35/-22 -JM20c -BWSne -Baf -I1/1p,0/200/251 -W1,black -Gwhite -Di -N2/0.25p,black -Na/0.5,black -Swhite > SA.ps

gmt makecpt -Cmag -T-10/30 -H > my.cpt
gmt surface ppp_amp.dat -R16/33/-35/-22 -JM20c -I1/1p,0/200/251 -GSouthAfrica_grd.nc -T0.25 -C0.1 -Vi
Long Lat Height
20.81 -32.38 3.462601451
23.99 -30.67 3.47238561
27.71 -25.89 2.983290468
19.22 -34.42 3.370191352
27.69 -25.89 2.809467594
25.54 -25.81 3.047883036
28.22 -25.75 3.370601204
28.22 -25.75 3.491404931
32.08 -28.8 2.386482489
17.88 -29.67 3.347240755
20.81 -32.38 3.018843543
30.38 -23.08 2.779844546
31.42 -28.29 2.419745172
28.67 -31.55 1.835212073
37.86 -46.88 10.3258571
28.22 -25.75 3.626294693
28.22 -25.75 3.588034193
26.72 -30.68 3.450797176
26.3 -29.1 1.810321089
27.43 -32.86 1.801976579
27.78 -25.64 3.479390519
28.73 -25.8 3.277078322
18.45 -34.35 2.622937276
26.51 -33.32 2.545416159
24.54 -32.25 2.302805262
28.37 -26.51 3.308374094
27.69 -25.89 2.069509857
30.07 -30.15 0.466945394
24.81 -28.74 3.915630899
29.42 -30.57 1.299706356
27.77 -26.08 3.266030423
27.24 -27.66 3.85353708
18.73 -32.46 6.780467738
29.45 -25.77 2.199781941
39.99 -29.21 3.071521361
30.96 -25.48 2.896929353
28.33 -28.25 3.522047204
26.74 -26.93 1.46070852
23.37 -34.06 1.786851179
28.93 -24.01 3.291937952
28.28 -25.73 4.369096225
22.75 -29.67 3.76435148
29.47 -23.92 4.714191319
30.76 -30.29 2.10941761
17.88 -29.67 3.974042045
31.29 -29.34 4.746402624
20.81 -32.38 2.731779255
26.74 -27.98 3.802077695
19.45 33.65 4.360541202
28.34 -26.2 3.261933725
28.33 -28.25 2.492962693
19.76 -31.48 3.450588564
18.47 -33.95 4.163197896
30.95 -29.97 1.505421449
27.83 -33.04 3.704138425
27.7 -23.69 3.394110991
29.41 -25.16 2.970443754
22.38 -34 3.746083503
30.58 -29.07 4.720041485
18.16 -32.97 3.7565446
29.78 -28.56 2.248874066
31.13 -23.95 3.142481019
25.61 33.99 4.184718732
22.57 -32.35 3.293254127
21.26 -28.41 7.080971271
30.38 -29.6 3.505024481

image
image797×684 47.2 KB

2

What errors did you have?

3

Good evening, Please sorry for replying you late.
below is the warning gotten
[INFORMATION]: Cartesian input grid
surface [INFORMATION]: Cartesian input grid
surface [INFORMATION]: Grid domain: W: 16 E: 33 S: -35 N: -22 n_columns: 17 n_rows: 13 [gridline registration]
surface [WARNING]: Your grid dimensions are mutually prime. Convergence is very unlikely.
surface [INFORMATION]: Hint: Choosing -R15/35/-36/-20 [n_columns = 20, n_rows = 16] might cut run time by a factor of 4.1744444

4

You are gridding the data but you are then not plotting the grid. Unless you did not show us that part of the script. You can plot the grid as contours (grdcontour) or image (grdimage), for instance.

5

Hello sir, Thanks for your response, I am sorry for replying late, I am on vacation and i traveled to my Country. the script I show is the script Iused. Please can you direct me to the GMT 6.1.1 documentation I can read to have an idea to plot the surface map rather then gridding.
Hope to hear from you soon
Thanks and best regards .

6

The tutorial maybe?