How to use same colors inn all figures when making several figures with a loop

I have created a loop that makes several figures. When I apply "rand(1,3)) in the loop below, each figure gets different colors. Do you know how I can change the loop below to so that the colors are the same in every figure?

Alder = {'<20', '2029','3039','4049','5059','6069','>70', 'all'};
Vars = {gjG, gjR, gjI, gjDI, gjBV, GtoDI, GtoBV, RtoDIplusR, ItoG, RtoG, GtoI};
Vars2 = {'gjG', 'gjR', 'gjI', 'gjDI', 'gjBV', 'GtoDI', 'GtoBV', 'RtoDIplusR', 'ItoG', 'RtoG', 'GtoI'};
Aar = {'2011', '2012', '2013_1', '2014_1', '2014_s2', '2014_s5'};
n = length(Vars);
nAar = length(Aar);
for iVars = 1:n;
  aVars = Vars{iVars};
figure,title(Vars2{iVars}); 
hold on
for iAar = 1:nAar
  plot(aVars(11,:,iAar), 'color', rand(1,3));
set(gca, 'XTickLabel',Alder)
legend((Aar),'location','NE','FontSize',10);
end
hold off
end

Answer 1

[the cyclist]

This line sets the color:

 plot(aVars(11,:,iAar), 'color', rand(1,3))

You could change that to

   plot(aVars(11,:,iAar), 'color', 'r')

for red, or

plot(aVars(11,:,iAar), 'color', [r g b])

where r,g, and b are numeric values to give any RGB color.

[Karl]

This approach gives the same result as I commented in the reply above. What you suggest give the same color for alle graphs in the same figure. I want different colors for each label in the figures, but that the labels in the different figures have the same colors. So "2011" should have a different color from "2012" ion each figure, and the "2011"-color should be equall accross all figures.

[the cyclist]

Ah. Several ways to do this. Here is one.

Define

randColors = rand(nAar,3);

outside your loop. Then use

plot(aVars(11,:,iAar), 'color', randColors(iAar,:))

to plot.

You might want to set the random number generator seed at the beginning of the code, so you get the same colors every time you run the code.

[the cyclist]

Randomly generated colors are often difficult to distinguish from each other. If you want to get more sophisticated, consider using this entry from the File Exchange:

http://www.mathworks.com/matlabcentral/fileexchange/29702-generate-maximally-perceptually-distinct-colors

[Karl]

What you suggested in the first post worked. Thanks! You are right about the colors.Not much difference!

[the cyclist]

You can try setting different random seeds at the beginning of your code, to see if you can find a better array of colors.

If you don't want to use random colors, you can try the approach that Image Analyst had in his answer, which is similar to my answer but takes advantage of built-in MATLAB color maps.

Answer 2

[Azzi Abdelmalek]

Use

plot(aVars(11,:,iAar), 'color', [1 0 1]);

[Karl]

What you suggest give the same color for alle graphs in the same figure. I want different colors for each label in the figures, but that the labels in the different figures have the same colors. So "2011" should have a different color from "2012" ion each figure, and the "2011"-color should be equall accross all figures.

Answer 3

[Image Analyst]

Make up a table of colors. It should be N rows (for N colors that you want to use) by 3 columns (a red, a green, and a blue value). The numbers should go from (0,0,0) for black up to (1,1,1) for white. If you want, you can use some built in colormaps, like lines:

numberOfColors = 15; % Whatever you want.
myColorMap = lines(numberOfColors);  % Use lines(), jet(), winter(), or whatever.

Whenever you want to plot the curve in the k'th color, you just do

plot(x, y, 'Color', myColorMap(k, :));

Do this for every axes that you want to plot in.

[Karl]

That worked. Thanks!