Multiple plots on the same figure julia

Question

I am writing a Julia program which iteratively runs another function, and will give me two sets of results. I want to plot these results and right now what I am doing is to plot the results of each for loop separately which gives me about 20 plots for the example below: Say something like this:

for i in 1:10
    x1,y1 = first_function(a,b,c)
    plot(x1,y1)
end
for j in 1:10
    x2,y2 = second_function(a,b,c)
    plot(x2,y2)
end

I have tried to use the plot!() command instead but this gives me all 20 plots on the same plot, which I don't want. What I would like to do is to plot the results of both functions on the same plot, for each iteration. For instance I want 10 plots, one for each iteration where each plot has results of both first_function() as well as second_function. I have tried the following instead:

for j in 1:10
    x1,y1 = first_function(a,b,c)
    x2,y2 = second_function(a,b,c)
    plot!(x1,y1)
    plot!(x2,y2)
end

However, this doesn't seem to work either.

EDIT: Based on an answer I received, I was able to figure out that the following does the trick:

for i in 1:10
    x1,y1 = first_function(a,b,c)
    x2,y2 = second_function(a,b,c)
    plot(x1,y1)
    plot!(x2,y2)
end

This generates a new plot at the end of each iteration of the loop, which is what I wanted.

score 4 · Accepted Answer · answered Nov 17 '21 at 13:23

4

As you have found out, plot() creates a new plot, while plot!() plots onto the currently active plot.

All you need to do is be explicit about when you want to do what, and if you're using plot!() also be explicit about which plot object you want to plot to. So something like:

p1 = plot()
p2 = plot()

for i in 1:10
    plot!(p1, first_function(a, b, c)...)
    plot!(p2, second_function(a, b, c)...)
end

then p1 should have 10 lines showing the result of first_function, and p2 10 lines with results of the second function.

It is not clear to me whether you want both of these plots to appear on the same figure, but if you do then plot(p1, p2) will create a figure with two subplots.

answered Nov 17 '21 at 13:23

Nils Gudat

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1

I wanted the first iteration of both functions in one plot, second iterations for both in a different plot and so on, with a total of 10 plots (in this case). So this isn't exactly what I wanted. However, based on what you said I did try something else instead which I've mentioned as an edit to my post, and that seems to work. Thanks! – newtothis Nov 17 '21 at 13:27
1

Good to hear and sorry for not reading properly - you clearly said you wanted 10 plots! You might have figured this out already but just for posterity if you actually want to see the plots at every loop iteration you have to `display` them, as the loop won't return the plot object. – Nils Gudat Nov 17 '21 at 13:34
Yes, I did realise that and added `display`. Thanks! – newtothis Nov 17 '21 at 14:09
1

Given the question is basically answered now, it might be good to just accept my answer to close it, even though the final answer is in your question! – Nils Gudat Nov 17 '21 at 16:13

Multiple plots on the same figure julia

1 Answers1