gmt-fork/test/grdfft/out_taper.sh

#!/usr/bin/env bash
# Testing gmt grdfft -N+m mirror reflection and -N+e edge-point symmetry

ps=out_taper.ps
gmt set GMT_FFT kiss

# Create an egg-carton input grid
gmt grdmath -R0/300/0/200 -I1 X 5 MUL COSD Y 10 MUL SIND MUL = t.nc
gmt grdfft t.nc -N512/384+m+t50+wtmp1+l -E > /dev/null
gmt grdfft t.nc -N512/384+e+wtmp2+l -E > /dev/null
cat << EOF > box
0	0
300	0
300	200
0	200
EOF

scl=0.008
x=$(gmt math -Q 512 2 DIV $scl MUL =)
xoff=$(gmt math -Q 512 300 SUB 2 DIV $scl MUL NEG =)
yoff=$(gmt math -Q 200 $scl MUL 0.5 ADD =)
yoffe=$(gmt math -Q 384 $scl MUL 0.5 ADD =)
gmt makecpt -Cpolar -T-1/1 > t.cpt
gmt grdimage t.nc -Jx${scl}i -Ct.cpt -P -Ba -BWSne -K > $ps
gmt grd2xyz t_tmp2.nc | awk '{if ($2 == 100) print $1, $3}' > tmp
R=$(gmt info tmp -I10/3)
gmt psxy $R -JX3.5i/1.6i -O -K -W1p,green -Bxaf -Byafg10 -BWSne -X3i tmp >> $ps
gmt psxy -R -J -O -K -W0.5p,- << EOF >> $ps
>
0	-3
0	3
>
300	-3
300	3
EOF
# mirror and taper
gmt grdimage t_tmp1.nc -Jx${scl}i -Ct.cpt -Ba -BWSne -O -K -X-3i -Y${yoff}i >> $ps
gmt psxy -Rt_tmp1.nc -J -O -K -L -W2p box >> $ps
echo "400 192 Mirror symmetry" | gmt pstext -R -J -O -K -N -F+jLM+f16p -D0.5i/0 >> $ps
echo "400 192 50% outward taper" | gmt pstext -R -J -O -K -N -F+jLM+f16p -D0.5i/-0.3i >> $ps
# edge-symmetry and taper
gmt grdimage t_tmp2.nc -J -Ct.cpt -Ba -BWSne -O -K -Y${yoffe}i >> $ps
gmt psxy -Rt_tmp2.nc -J -O -K -L -W2p box >> $ps
gmt psxy -R -J -O -K -W2p,green << EOF >> $ps
-105	100
410	100
EOF
echo "400 192 Point symmetry" | gmt pstext -R -J -O -K -N -F+jLM+f16p -D0.5i/0 >> $ps
echo "400 192 100% outwardtaper" | gmt pstext -R -J -O -K -N -F+jLM+f16p -D0.5i/-0.3i >> $ps
gmt psscale -Ct.cpt -Dx${x}i/${yoffe}i+w4i/0.1i+h+jTC -O -K -B0.5 >> $ps
gmt psxy -R -J -O -T >> $ps