Multible y-axix (more than two) in wxdraw2d()

[ReneSci]

Would it be possible to implement some gnuplot code that makes plots like this possible?

https://stackoverflow.com/questions/27390317/how-to-plot-multiple-y-axes

[gunterkoenigsmann]

Two axis are possible - and I use them frequently:

wxdraw2d(
    explicit(sin(x),x,0,2*π),
    xlabel="x [rad]",
    xlabel_secondary="x [°]",
    xrange_secondary=[0,360],
    xaxis_secondary=true,
    xtics_secondary=true,grid=[5,5]
);

But multiplots aren't currently possible for maxima's png and pngcairo output that wxMaxima uses - and what draw is missing is the possibility to add raw gnuplot commands: There is gnuplot_preamble, but you cannot insert a

set ytics offset  -8, 0

into exactly the current place in the gnuplot file maxima creates. Both features would be possible feature requests for the maxima project, though: At least the latter I would use from time to time.

[daute]

Well - if the function can be expressed using Gnuplot commands and you just want to include it in a wxMaxima worksheet, the following trick may help:

(Code taken from the Stackoverflow page you referenced).

Here I am plotting the function y=0 (with x= 0-10), so it is not shown - and afterwards I insert the gnuplot commands using gnuplot_postamble. Quotes need to be escaped, of course.

wxplot2d(0,[x,0,10],[gnuplot_postamble,"
set multiplot
clear
set xrange[0:10]

# We need place to the left, so make the left margin 30% of screen
set lmargin screen 0.3

##### first plot

set ytics 0.4
set yrange[-1.2:1.2]

set ylabel \"Voltage\" textcolor rgb \"red\"

plot sin(x)


##### Second plot

set ytics 1
set yrange[-3:3]

set ytics offset  -8, 0
set ylabel \"Current\" offset -8, 0 textcolor rgb \"green\"

plot 3*cos(x) linecolor 2

##### Third plot

set ytics 0.5
set yrange[-1.5:1.5]


set ytics offset -16, 0
set ylabel \"Power\" offset -16, 0  textcolor rgb \"blue\"
plot 3*sin(x)*cos(x) linecolor 3

unset multiplot"])$