# How to plot data with >2 dimensions?

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Steven Que on 12 Oct 2020
Edited: Rik on 12 Oct 2020
I have a variable of size 3x5x10000 and I want to plot this. The idea is that there are 5 trees which grow over 10000 timesteps in 3 different scenarios.
How could I get this in a plot which shows the growth of 5 trees over 10000 timesteps in 1 plot, and have 3 plots in total for each different scenario? The plot function can seemingly only use data with 2 dimensions.

Alan Stevens on 12 Oct 2020
Look at documentation on plot3

Rik on 12 Oct 2020
Apart from plot3 (as Alan suggested), you may also consider using subplot to divide the different scenarios and using hold to plot the multiple trees in a single axes (or the reverse of course). The fact that your variable is 3D doesn't mean you need to actually plot your data in 3 dimensions.

Steven Que on 12 Oct 2020
When I use subplot and plot, I put:
time = 1:n; % Here n is the amount of timesteps, so 10000 in this case
subplot(1,3,1) % Use a 1x3 plot and define whats on #1 with plot
plot(time,dh(1,:),'b') % plot time vs the variable dh, 1st row and all columns
This gives me the error that the vectors are not the same length, time = 1:10000 and my dh looks like this:
val(:,:,1) =
2.2321 2.6510 2.9316 3.1485 3.3277
2.2321 2.6510 2.9316 3.1485 3.3277
2.2321 2.6510 2.9316 3.1485 3.3277
val(:,:,2) =
2.2322 2.6511 2.9317 3.1486 3.3278
2.2322 2.6511 2.9317 3.1486 3.3278
2.2322 2.6511 2.9317 3.1486 3.3278
% This small 3x5 repeats itself n times, so 10000 times.
How do I get row 1, column 1, for every of these 10000 in the plot?
When I try to use
plot(1,1,:)
It says that the data cannot have more than 2 dimensions.
The end goal is to have the rows separated per subplot, and have every column as a different line per subplot.
Rik on 12 Oct 2020
Use dh(1,1,:) instead, that will select the first element from each 3x5 block. If plot still complains, use squeeze to reduce the dimensionality of your array.
dh=rand(3,5,10000);
time=1:size(dh,3);
n=0;
for scenario=1:size(dh,1)
ax=subplot(1,3,scenario);
cla(ax);%only for debugging: clear axes contents
hold(ax,'on');
for tree=1:size(dh,2)
name=sprintf('tree %d',tree);
plot(time,squeeze(dh(scenario,tree,:)),'DisplayName',name,'Parent',ax);
end
hold(ax,'off');
title(sprintf('scenario %d',scenario))
legend(ax)
end