Custom color map for plotting matrix values
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Here's an example of what I want to do, but instead of a loop for the plot, I want to feed in plot(x,y); instead of plot(x,y(i,:))
% Define vector values
n = 101; N = 30;
x = linspace(0,2,n);
y = ((-N/2:N/2)').*x.^4;
% Plot
figure; hold on;
% Prepare colormap
Color1 = [0,0.5,1];
Color2 = [1,0.5,0];
for i = 1:N
Col = Color1 + (Color2 - Color1)*(i-1)/(N-1);
plot(x,y(i,:),'Color',Col);
end
Where, I want to replace
for i = 1:N
Col = Color1 + (Color2 - Color1)*(i-1)/(N-1);
plot(x,y(i,:),'Color',Col);
end
with
for i = 1:N
Col(i,:) = Color1 + (Color2 - Color1)*(i-1)/(N-1);
end
plot(x,y,'Colors',Col);
with the following plot as the result.

2 Comments
Adam
on 28 Jul 2017
What are you actually trying to do? Colourmaps don't apply to line plots whose default colours are controlled by the 'ColorOrder' property of the colourmap.
But your 'Col' variable is just a 3-element vector - i.e. a single colour, so if you just want to set all lines to the one colour then that is trivial, but doesn't count as a colourmap so I assume something is missing from your example?
Accepted Answer
Image Analyst
on 30 Jul 2017
I think you probably want scatter(). With scatter(), you can pass in an array of colors so that you can vary each data point's color on a point-by-point basis.
If you really want color order, see my attached demo, but I don't think you want that over scatter.
3 Comments
Image Analyst
on 30 Jul 2017
OK, now that I see what you want in your plot you just inserted I guess you want colored lines so scatter() can't do that.
But did my colororder demo help you? Look - I'll even include a screenshot from it:

Look like what you want, right?
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