I am trying generate a pie chart using GNUPLOT, I have already generate the plot, and I have assigned colour to the legend using an array. This is the code, I have used this question as reference
script.sh
#!/usr/bin/gnuplot
set terminal pngcairo nocrop enhanced size 800,400 font "Siemens Sans,8"
set output 'output.png'
filename = 'source.dat'
rowi = 1
rowf = 2
# obtain sum(column(2)) from rows `rowi` to `rowf`
set datafile separator ','
stats filename u 2 every ::rowi::rowf noout prefix "A"
# rowf should not be greater than length of file
rowf = (rowf-rowi > A_records - 1 ? A_records + rowi - 1 : rowf)
angle(x)=x*360/A_sum
percentage(x)=x*100/A_sum
# circumference dimensions for pie-chart
centerX=0
centerY=0
radius=0.2
# label positions
yposmin = 0.0
yposmax = 0.95*radius
xpos = 1.5*radius
ypos(i) = yposmax - i*(yposmax-yposmin)/(1.0*rowf-rowi)
#-------------------------------------------------------------------
# now we can configure the canvas
set style fill solid 1 # filled pie-chart
unset key # no automatic labels
unset tics # remove tics
unset border # remove borders; if some label is missing, comment to see what is happening
set size ratio -1 # equal scale length
set xrange [-radius:2*radius] # [-1:2] leaves space for labels
set yrange [-radius:radius] # [-1:1]
#-------------------------------------------------------------------
pos = 0 # init angle
colour = 0 # init colour
colors = "blue red"
# 1st line: plot pie-chart
# 2nd line: draw colored boxes at (xpos):(ypos)
# 3rd line: place labels at (xpos+offset):(ypos)
plot filename u (centerX):(centerY):(radius):(pos):(pos=pos+angle($2)):(colour=colour+1) every ::rowi::rowf w circle lc var,\
for [i=0:rowf-rowi] '+' u (xpos):(ypos(i)) w p pt 5 ps 4 lc rgb word(colors,i+1),\
for [i=0:rowf-rowi] filename u (xpos):(ypos(i)):(sprintf('%05.2f%% %s', percentage($2), stringcolumn(1))) every ::i+rowi::i+rowi w labels left offset 3,0
The source file to generate the pie chart is this
source.dat
"Tipo","Valor"
"Periodo laboral",723
"Periodo no laboral",81
And when I run the script I get a output.png
file that looks like this
output.png
As you can see, the pie chart colours don't fit the legend colour. This is because I can easily set the legend colour thanks to the for
index, but for generating the pie chart I am iterating through the every
clause so I can't get an index. I have also tried something like:
plot filename u (centerX):(centerY):(radius):(pos):(pos=pos+angle($2)):(colour=colour+1) every ::rowi::rowf w circle lc rgb(word(colors, colour)),\
but I have the following error:
"gnuplot/piechart.sh", line 49: warning: This plot style does not work with 6 cols. Setting to xyerrorbars
Could you help me please? Thanks in advance.
UPDATED
I think I have taken a step. I have removed the (colour=colour+1)
part of the plot command, and now I can set an specific color that way
plot filename u (centerX):(centerY):(radius):(pos):(pos=pos+angle($2)):(colour=colour+1) every ::rowi::rowf w circle lc rgb word(colors,colour+1),\
But this draw the pie chart completly blue, and I still need a index or something because it seems colours
don't change its value.