如何将gnuplot极轴限制在180度范围内？

我试图使用gnuplot绘制+/-90度范围内扬声器的离轴响应。我的工作很好，几乎完全是因为

我想扩展它，这样它只显示向前的“180”范围，但我不知道如何做到这一点&希望能有一些指点

这是到目前为止我的代码

gnuplot <<EOF
set terminal pngcairo size ${WIDTH}/2,${HEIGHT}/2 font ',10'

set polar
set angle degrees
set size ratio 1
set tmargin 3
set bmargin 3

set style line 11 lc rgb 'gray80' lt -1
set grid polar ls 11

unset border
unset xtics
unset ytics

set xrange [-30:30]
set yrange [-30:30]
set key

r=1
set rrange [0:r]
set rtics 0.166 format '' scale 0
set label '0°' center at first 0, first r*1.05
set label '180°' center at first 0, first -r*1.05
set label '-90°' right at first -r*1.05, 0
set label '+90°' left at first r*1.05, 0

set for [i=1:5] label at first r*0.02, first r*((i/6.0) + 0.03) sprintf("%d dB", -30+(i*5))
unset raxis

set key outside top right
set style line 11 lw 2 

set output '${PREFIX}_polar.png'
set multiplot layout 1,2 title "Circular Polar Response"
set title "Normalised"
plot '${PREFIX}_norm_polar_1000.txt' t '1k'  w lp ls 11 lt 1 pt -1 , \
     '${PREFIX}_norm_polar_2000.txt' t '2k'  w lp ls 11 lt 2 pt -1 , \
     '${PREFIX}_norm_polar_4000.txt' t '4k'  w lp ls 11 lt 3 pt -1 , \
     '${PREFIX}_norm_polar_8000.txt' t '8k'  w lp ls 11 lt 4 pt -1 , \
     '${PREFIX}_norm_polar_16000.txt' t '16k' w lp ls 11 lt 5 pt -1 
set title "Unnormalised"
plot '${PREFIX}_polar_1000.txt' t '1k'  w lp ls 11 lt 1 pt -1 , \
     '${PREFIX}_polar_2000.txt' t '2k'  w lp ls 11 lt 2 pt -1 , \
     '${PREFIX}_polar_4000.txt' t '4k'  w lp ls 11 lt 3 pt -1 , \
     '${PREFIX}_polar_8000.txt' t '8k'  w lp ls 11 lt 4 pt -1 , \
     '${PREFIX}_polar_16000.txt' t '16k' w lp ls 11 lt 5 pt -1 

EOF

---

如果使用与rrange设置相矛盾的xrange和yrange设置，Gnuplot会感到困惑。这可能就是为什么会忽略yrange设置的原因

然后，还必须使用

设置大小比率-1

，以便在x和Y范围内获得相同的缩放比例。当仅绘制上两个象限时，使用

设置大小平方

将获得错误的纵横比

set terminal pngcairo font ',10'

set polar
set angle degrees
set size ratio 1
set lmargin 8
set style line 11 lc rgb 'gray80' lt -1
set grid polar ls 11

unset border
unset tics

set xrange [-1:1]
set yrange [0:1]
set size ratio -1

r = 1
set rtics 0.166 format '' scale 0
set label '0°' center at first 0, first r*1.05
set label '-90°' right at first -r*1.05, 0
set label '+90°' left at first r*1.05, 0

set for [i=1:5] label at first r*0.02, first r*((i/6.0) + 0.03) sprintf("%d dB", -30+(i*5))
unset raxis

set key outside top right

set output 'polar.png'
plot 'norm_polar_1000.txt' w lp ls 1 t '1k'

---

我认为这是可行的，但对情节没有影响

set terminal pngcairo font ',10'

set polar
set angle degrees
set size ratio 1
set lmargin 8
set style line 11 lc rgb 'gray80' lt -1
set grid polar ls 11

unset border
unset tics

set xrange [-1:1]
set yrange [0:1]
set size ratio -1

r = 1
set rtics 0.166 format '' scale 0
set label '0°' center at first 0, first r*1.05
set label '-90°' right at first -r*1.05, 0
set label '+90°' left at first r*1.05, 0

set for [i=1:5] label at first r*0.02, first r*((i/6.0) + 0.03) sprintf("%d dB", -30+(i*5))
unset raxis

set key outside top right

set output 'polar.png'
plot 'norm_polar_1000.txt' w lp ls 1 t '1k'