Shade below a graph above certain value

Hi,

I'd like to add shade into the region right of the vertical line and below the graph. I have a set of data y, the code is following:

figure;
hold all
[p, q] = ksdensity(y)
plot(p, q)
y_star = 1.5;
line([y_star, y_star], get(gca, 'ylim'));

Thank you very much!

Answer 1

[Star Strider]

Yopu did not choose to share the data that created ‘p’ and ‘q’, so I created my own functions to test this code:

p = linspace(-3, 6);                                                        % Create Data
q = exp(-p.^2/5);                                                           % Create Data

figure
plot(p, q)
y_star = 1.5;
line([y_star, y_star], get(gca, 'ylim'));
hold on
yq = find(p <= y_star, 1, 'last');
patch([p(yq:end) fliplr(p(yq:end))], [zeros(1,numel(p(yq:end))) fliplr(q(yq:end))], 'g')
hold off

This should work with your ‘p’ and ‘q’ vectors. Choose the colour you want for the patch area.

[Walter Roberson]

See also https://www.mathworks.com/help/matlab/ref/fill.html fill()

You might also like https://www.mathworks.com/matlabcentral/fileexchange/13188-shade-area-between-two-curves

[Guanyu Zhou]

It works! Thank you very much!

[Star Strider]

As always, my pleasure!