Colour of legend doesn't change?
5 views (last 30 days)
Show older comments
Muhammad Fakhruddin Abd Rahim
on 14 Nov 2019
Commented: Muhammad Fakhruddin Abd Rahim
on 14 Nov 2019
This is my plotting code
%%
%The Spectrum
figure(5);
S1 = (a.^2).*0.5;
plot(f,S1,'b');
hold on;
plot(f,S,'r');
legend ('Initial spectrum','JONSWAP Spectrum');
title('The Spectrum')
xlabel('Frequency (Hz)')
ylabel('Wave spectrum in (m^2/s)')
When I run it I got this one :
The colour of the legend is the same. How can I change it?
4 Comments
Accepted Answer
Walter Roberson
on 14 Nov 2019
Your a looks to have multiple columns, so S1 would have multiple columns.
plot(f,S1,'b');
would generate one line object per column.
3 Comments
Walter Roberson
on 14 Nov 2019
If S1 has 2257 columns, then plot(f,S1) will produce 2257 line() objects. When you legend() providing only two texts, then by default legend() will pick up the first two of those, both of which are the ('b') line() objects, so both of them are given blue entries in the legend text.
You have some options:
1)
H1 = plot(f,S1,'b');
hold on;
H = plot(f,S,'r');
legend([H1(1), H(1)], 'Initial spectrum','JONSWAP Spectrum');
2) It is possible to merge all of the first drawing into a single line object by putting NaN between the segments to be drawn, such as
Stemp = S;
Stemp(end+1,:) = nan;
and then plotting Stemp(:) against a version of f that has been adjusted to have appropriate number of copies of the coordinates
3) Leave your existing graphics, but afterwards do
L = plot(nan, nan, 'b', nan, nan, 'r');
legend(L, 'Initial spectrum','JONSWAP Spectrum')
More Answers (0)
See Also
Categories
Find more on Legend in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!