colour code plotted data according to column

I have a 20000*20 matrix of data and I'd like to colour code the points depends on the column. e.g. data points from column one are blue, from column two are red...etc all the way to column 20.

I saw similiar answer from this post but for-loop doesn't work well for large amount of data points

https://uk.mathworks.com/matlabcentral/answers/600517-color-code-plotted-data-according-to-value-in-un-plotted-column

I wonder if this can be done more efficiently?

Answer 1

[Riccardo Scorretti]

Simply like that, if I correclty understand your question:

% Generate some data
p = linspace(0, 2*pi, 20000);
data = zeros(numel(p), 20);
for n = 1 : 20
  data(:,n) = n*sin(p);
end

figure
plot(data);

[Yuchun Ding]

that was quick! Thanks a lot!

not exatly what I meant but you inspired me to find the right answer: plot and hold on the data column by column where data points from each column are assigned a colour of my choice. By default I think matlab colour code them using jet colourmap.