Consistent fonts in gnuplot?

Question

I have the following script in gnuplot which works fine except for some font issues.

#!/usr/bin/env gnuplot

# setup
set terminal pngcairo enhanced color notransparent background rgb "white"
set output "temp.png"
lm="Latin Modern Math" 

# range 
set xrange [-3*pi/2:3*pi/2]
set yrange [-1.5:1.5]

# labels  
set xlabel "{/Symbol q} (radian)" font lm
set ylabel "sin({/Symbol q}), cos({/Symbol q})" font lm
set title "Simple Sinusoid" font lm

# plot
plot sin(x) with lines linecolor rgb "red" title "sine", 0  title ''
set output

As you can see:

1. The font used for the theta symbol is inconsistent with the text 'sin' and 'radian' on the axes.
2. The 'sine' appearing in the legend is also rendered in a different font. I tried using the font command after the title but it did not work

Any ideas? Thanks!

Edit The reason I want to use "Latin Modern" is because of consistency with the rest of the document (into which this will be included) which uses the same font.

Answer 1

You are probably looking for set key font lm. Furthermore, gnuplot should be able to understand utf-8, so you can directly place θ in your labels. Since I don't have 'Latin Modern Math', I used "Lucida Graphic Italic" and "Courier New" for illustration. Another option would be to specify font in the terminal, e.g. set terminal pngcairo font "<whatever>". Check help pngcairo.

Code:

### set fonts
reset session

set terminal pngcairo enhanced color notransparent background rgb "white"
set output "temp.png"
myFont = "Lucida Graphic Italic"
myFont2 = "Courier New"

# range 
set xrange [-3*pi/2:3*pi/2]
set yrange [-1.5:1.5]

# labels  
set title "Simple Sinusoid" font myFont
set xlabel "θ (radian)" font myFont
set xtics font myFont2
set ylabel "sin(θ), cos(θ)" font myFont
set ytics font myFont2

set key font myFont

# plot
plot sin(x) with lines linecolor rgb "red" title "sine", 0  title ''
set output
### end of code

Result: