Question

What I want:

Different coloured points on a plot and to have the points in a legend with their respective colours.

I tried this:

I have created a struct which contains x, y values of points. With these points I hope to plot points on an image so I can see where they are. However, as I’m using a struct I can’t get the plot to make the points in different colours. With the for loop I tried to coax matlab in creating multiple plots, and hopefully different lines, which I could then assign to different colours of my choosing.

Code:

img = imread('retinotopische map V1M Base clean.bmp');            

hold on;                     
image([0.825 4.61],[-2.85 ,-8.25],img);

for A =  1:B
    plot( [c(A).Lateral],[c(A).Bregma],'o','MarkerSize',10);    
    plot( [c(A).Lateral],[c(A).Bregma],'.','MarkerSize',10);    
end

Answer 1

You can change the colour using the ‘Color’ option:

   img = imread('retinotopische map V1M Base clean.bmp');            

    hold on;                     
    image([0.825 4.61],[-2.85 ,-8.25],img);

    for A =  1:B
       plot( [c(A).Lateral],[c(A).Bregma],'o','MarkerSize',10, 'Color', [A/B, 0, 1 - A/B]);     
    end

‘Color’ lets you specify an RGB triple like [1 0 0] for red for example. You can use this to plot whatever colors you want. My example will plot them in like a gradient but you could also have totally different colours using say rand(1, 3) to get the triple? Or else make a colour matrix where you specify the exact order of colours you want like:

MyColours = [1 1 0;
             0 0 1;
             1 0 0;
             0.5 0.2 0.9]; %etc...

and then in your for loop:

plot( [c(A).Lateral],[c(A).Bregma],'o','MarkerSize',10, 'Color', MyColours(A, :));