How to make smooth curve on figure?

I have a matlab figure which has noisy data. I want to plot a smooth curve for those data. Can anyone help on this issue?

Answers (1)

The Savitzky-Golay filter (Signal Processing Toolbox sgolayfilt function) is probably best for your application:
F = openfig('smooth.fig');
x = get(get(gca, 'Children'), 'XData');
y = get(get(gca, 'Children'), 'YData');
x = x(~isnan(y));
y = y(~isnan(y));
b = sgolayfilt(y, 3, fix(length(y)/2));
hold on
plot(x, b, '-r')
hold off
Experiment with the filter polynomial order and frame length to get the result you want.

Asked:

on 6 Apr 2015

Answered:

on 6 Apr 2015

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!