I have the Gnuplot script below. All looks good except that in the right pie-chart the area that is highlighted with black diagonal lines should have a green background. Update: Thank you. I have now corrected the script. It should work now. Please try and run it again.
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reset
set terminal pngcairo size 1000,500 enhanced font 'Arial,14'
set output 'ATU20250410_Piechart_Q5.png'
set multiplot layout 1,2 title "Q5: Hvordan maales den samlede masse af en galaksehob?"
unset key
unset border
unset tics
set size square
set xrange [-1:1]
set yrange [-1:1]
set angle degrees
#Pie Chart 1: BEFORE
set title "Before Lecture"
unset object
unset label
#Q5F_b: 7 \u2192 (7/9)*360 = 280°
#Q5C_b: 2 \u2192 (2/9)*360 = 80°
set object 1 circle at 0,0 size 1 arc [0:280] fillstyle solid 1.0 fillcolor rgb "orange"
# Q5F_b
set object 2 circle at 0,0 size 1 arc [280:360] fillstyle solid 1.0 fillcolor rgb "green"
# Q5C_b
set label 1 "Q5F: 7" at -0.5, 0.8
set label 2 "Q5C (correct answer): 2" at 0.4, -0.6
plot [-1:1][-1:1] 1/0 notitle
#-------------------
#Pie Chart 2: AFTER
set title "After Lecture"
unset object
unset label
#Totals (based on selections across students):
#Q5B_a: 6 \u2192 154°
#Q5C_a: 6 \u2192 154°
#Q5F_a: 1 \u2192 26°
#Q5A_a: 1 \u2192 26°
#Total "slices" = 14 (sum of all mentions)
#Assign angles:
angle_b = 0
angle_c = angle_b + 154
angle_f = angle_c + 154
angle_a = angle_f + 26
#Q5B_a: solid green
set object 3 circle at 0,0 size 1 arc [angle_b:angle_c] fillstyle solid 1.0 fillcolor rgb "green"
#Q5C_a: base green (slightly smaller radius so it shows under pattern)
set object 4 circle at 0,0 size 0.999 arc [angle_c:angle_f] fillstyle solid 1.0 fillcolor rgb "green"
#Q5C_a: pattern overlay (full radius, transparent with black lines)
set object 7 circle at 0,0 size 1 arc [angle_c:angle_f] fillstyle pattern 6
#Q5F_a: orange
set object 5 circle at 0,0 size 1 arc [angle_f:angle_a] fillstyle solid 1.0 fillcolor rgb "orange"
#Q5A_a: purple
set object 6 circle at 0,0 size 1 arc [angle_a:360] fillstyle solid 1.0 fillcolor rgb "purple"
#Labels
set label 3 "Q5B (correct answer): 6" at -0.8, -0.5
set label 4 "Q5C (correct answer): 6" at -0.8, 0.6
set label 5 "Q5F: 1" at 0.35, -0.4
set label 6 "Q5A: 1" at 0.35, -0.1
plot [-1:1][-1:1] 1/0 notitle
unset multiplot
Transparency in this case is an attribute of the pattern fill. The command
set object 7 circle at 0,0 size 1 arc[angle_c:angle_f] fillstyle pattern 6
must instead read
set object 7 circle at 0,0 size 1 arc[angle_c:angle_f] fillstyle transparent pattern 6