I am trying to plot my shear-wave splitting parameters on GMT by using psxy, but I misunderstood something .
if legend is
45.50 54.50 30 1.0
I expected to have a line with an azimuth of 30 degrees from the vertical, but it seems I have more a line with an azimuth of 60 degrees from the vertical. I am not sure what is wrong with my pixy
gmt psxy legend -R$R -Sv0.2i+jc -W2.5p,red -X-0.05 -Y0.1
Thanks
Walid
use -SV (capital V) to get azimuth CW from North instead of angle CCW from East (-Sv), and I also suggest to use -SVB to get the stick/vector balanced on the center point, rather than pointing away from it, because splitting “fast axes” are orientational (0…180 deg) rather than directional (0…360 deg)
Hi!
I’m new to the community and I apologize if this is not the right place to ask this question.
I am trying to do the same (plot azimuth lines from SWS analysis), however, I cannot find a way to plot the lines balanced at the center point using -SVB or -SVb as specified in the documentation. Lines seem to start from the midpoint (event location).
This is the line I am using:
gmt psxy -R -J stationX.dat -SVB0c -Wthinner,limegreen -l"Events"+f15p -B > azimuth0.ps
Thank you very much!
Am not sure about your problem …
Are -R (region) and -J (projection) are defined ? It seems you’re creating a new .ps file (>)
Can you give a few lines of stationX.dat ?
Yes, -R and -J are defined: -R-104.65/-103.95/31.5/31.85 -JM10c
Here are a few lines of the .dat file:
-104.3 31.65 81.308 0.49388
-104.29 31.661 157.13 0.58367
-104.31 31.654 101.05 0.18367
-104.3 31.659 73.23 0.53265
-104.31 31.66 88.205 0.61224
-104.2 31.653 63.339 0.69388
Thank you!!
Have you looked at vectors attributes ?
Well, I just tool a look again and I definetely missed this:
In addition, all but circular vectors may take these modifiers:
+j just determines how the input x,y point relates to the vector. Choose from beginning [default], end, or center.
So my line now looks like:
gmt psxy -R-104.65/-103.95/31.5/31.85 -JM10c stationX.dat -SVB0c+jc -Wthinner,limegreen -l"Events"+f15p -B
and it works. However, I do get this Warning: 0c+j not a valid number and may not be decoded properly.
Thank you very much!
I’ll have a look at that. I think we check if the header size is > 0 but if no header (+b or +e) are requested one should be able to not give on or give 0.
You are mixing old GMT 4 syntax (B) with GMT 6 syntax (+jc) and the parser sees it as an old-GMT4 syntax and you get this (harmless) warning. I suggest you use GMT 6 syntax going forward, which in your case would be -SV0+s+jc.
Got it! This worked indeed, thank you very much!