Psxy/plot -Sq option +t/T modifiers

In the process of trying to calculate coordinates for equally spaced points along a line/track (every 25 km in the sample below), I noticed that the psxy / plot -Sq...:+t option isn’t producing the output that I expected (the angle is included, not just the cumulative distance) and the +T modifier results in a psxy error Option -S: Parsing failure.

  1. Is the +t modifier supposed to output the distance along the line/track and the annotation angle?
  2. Am I doing something wrong to get the parsing error with the +T modifier?
cat << EOL > tmp.txt
0.1 0.1
0.1 0.9
# with "+t" -> lon, lat, angle, distance
gmt psxy tmp.txt -R0/1/0/1 -JM6c -N -SqD25k:+LD+ttmp1.pts > /dev/null
# with "+T" -> parsing error
gmt psxy tmp.txt -R0/1/0/1 -JM6c -N -SqD25k:+LD+Ttmp2.pts > /dev/null

I’m using GMT 6.1.1 installed with homebrew on macOS 10.14

Thank you,

  1. Yes, it should output distance. The output is lon, lat, angle, distance for the development version. I will check whether this changed since 6.1.1. Edit: I am unable to reproduce the problem and get x,y, angle, label (distance) using both dev and 6.1.1.

  2. No, you’re not doing anything wrong. The +T option is defunct. The documentation was fixed in a recent issue, see for the discussion.

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I have fixed the problem that it resulted in an error. While +T is deprecated, it should at least default to +t behavior, which it now will do once my PR is merged.

Now merged into master. Thanks for the report.

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