Pspolar not showing polarity symbols. about gmt HOT 13 CLOSED

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from gmt.

@SquirrelKnight could you include the script or exact command you ran? It also helps if you include the images that are generated.

from gmt.

bathyfocmec_1_MT.pdf

I've attached a PDF of the figure generated by my script. It is fairly long, so I will include the relevant snippet.

if ($showpol == 1) then
awk 'NR==1 {print $12,$11,$13,$22,$23,$24,5,0,0}' $pol_file | gmt psmeca $region $projection -Sa2.5i -Z$depthscale -O -K -N>> $post_script_name #For HASH
set pol_lon = awk 'NR==1 {print $12}' $pol_file #For HASH
set pol_lat = awk 'NR==1 {print $11}' $pol_file #For HASH
awk '{if (NR!=1) {print $1,$2,$3,$4}}' $pol_file | gmt pspolar $region $projection -D$pol_lon/$pol_lat -N -M2.5i -Sc0.4 -T -h1 -O -K >> $post_script_name
endif

The script essentially plots the focal mechanism in question, and then overlays the poles on top of the focal mechanism. pspolar did work for me with an older version of GMT on CentOS using this exact code, so I'm not sure what changed, and unfortunately there are no errors output when running my script.

from gmt.

I'd like to note that upon looking at the figures very carefully, you can actually see dots 1 px large for the polarities (only after converting from ps 2 pdf). When zooming in on those dots, they don't become any larger. I also tried completely removing GMT and reinstalling with brew, but had no success after doing so.

from gmt.

@SquirrelKnight Can you give us a minimal example to reproduce this issue?

There are so many variables (e.g. $pol_lon) in the example you posted 20 days ago, which are meaningless to us.

A minimal example should look like this:

gmt psmeca -Fo -R85/89/25/50 -JX7i -P -M -Sm4i -N  -L -K -G150 -T0 << EOF > test.ps
87  35 -0.26 -0.71 0.97 -0.20 -0.61 2.60 27  0    0
EOF

gmt pspolar -R -J -D87/35 -M4i -N -Sc0.3i -Qe -B0 -O << EOF >> test.ps
1 147.8 53 c
2 318.6 53 c
3 311.9 53 c
EOF

from gmt.

Hi,

I have made a small script and have also realized what the problem might be.

`set min_lon = "-129.5"
set max_lon = "-126.5"
set min_lat = "48.5"
set max_lat = "50"
set projection = "-JM14c"
set boundaries = "-Bxf0.25a0.5 -Byf0.25a0.5 -BWSne"
set region = "-R$min_lon/$max_lon/$min_lat/$max_lat"
set pol_file = "Event1_pol_HASH.txt"
set post_script_name = "test_pol.ps"

set pol_lon = -127.69666
set pol_lat = 49.67583
echo $pol_lon' '$pol_lat
gmt psmeca $region $projection -P -M -Sa4i -N -L -K -G150 -T0 << EOF > $post_script_name #For HASH
-127.69666 49.67583 27.690 9 30 -98 8 0 0
EOF
gmt pspolar -R -J -D$pol_lon/$pol_lat -M4i -N -Sc0.3i -T -Qe -O << EOF >> $post_script_name
FLYN 73.08 104.71 c
HSNT 86.96 97.41 c
MTCH 81.97 96.36 c
PLMP 88.97 98.98 c
SJ06 177.47 96.15 c
SJ07 183.04 99.01 c
SJ20 154.15 105.25 d
SJ21 194.61 100.38 d
SJ23 180.47 107.51 d
SJ24 167.73 110.96 c
SJ25 156.46 114.20 c
SJ26 206.98 98.54 c
SJ27 202.34 101.72 d
SJ29 191.94 110.32 d
SJ31 163.71 121.47 c
SJ32 214.74 102.30 c
SJ33 210.53 107.01 d
SJ34 205.28 113.51 c
ZBLS 59.99 100.72 c
EOF`

It looks like because my data has takeoff angles higher than 90 degrees, they will not plot (the stations will, but the polarity circles will not). In this case, it is functionality I would like to see added. In the meantime, I believe by subtracting 90 from any takeoff angles higher than 90, and by subtracting 180 from the azimuth, I should be able to achieve similar results. Is that correct?

from gmt.

This issue has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed if no further activity occurs within 7 days. Thank you for your contributions.

from gmt.

Note that your scale for psmeca is 4i which is scaled to a magntidue 5 earthquake, where as scale of pspolar is not. i.e., to get the correct projection, you have to scale your pspolar bubble as follows;
new_size=4/5*magnitude of the current event

example shell code
mag=2.5
ball_size='4i'
polar_ballsize=echo "scale=3; ${ball_size::${#ball_size}-1}*$mag/5" | bc

gmt pspolar -R -J -D$pol_lon/$pol_lat -M$polar_ballsize -N -Sc0.3i -T -Qe -O << EOF >> $post_script_name

I also suggest you use -V -P -K flags to check for bugs in your code.

from gmt.

@79seismo The size of the beachball is 4 inch, and not scale to the magnitude 5, since he uses -M option.

As what he said, the problem is that pspolar only plots polarities which take off from lower hemisphere, and ignore all upper-hemisphere polarities.

from gmt.

Is there a solution to this problem? Can you project up-going rays to the lower focal hemisphere? I think the solution is projecting the up-going ray to the lower focal sphere as given in Udias et al. in Source Mechanisms of Earthquakes: Theory and Practice, pp.112. i.e., Your new coordinates in the focal sphere should be back azimuth (instead of the azimuth) and 180-original up-going take off angle. This is because you're projecting the intersection point of the up-going ray and the focal sphere through the center of the focal sphere to the lower hemisphere.

from gmt.

This issue has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed if no further activity occurs within 7 days. Thank you for your contributions.

from gmt.

This issue has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed if no further activity occurs within 7 days. Thank you for your contributions.

from gmt.

It turns out this is a pspolar bug and should be fixed in #2461.

from gmt.