Smoothing curve plot with some data points

11 views (last 30 days)
hello, everybody
I have these data and I hope to plot them with smooth line.
Is it possible to create a smooth curve through these data points? I tried polybuffer function and it looks better.
But for data smoothing I failed using interpolation due to drastic chanhge of data points.
However, I think there is some ways I think. If possible please help me some.
x = [-27.59;-32.36;-32.36;-24.99;-25.12;-32.62;-37.62;-42.62;-37.62;-37.62;-40.11;-40.11;-37.61;-33.36;-29.11;-27.11;-25.11;-20.61;-14.36;15.64;45.64;158.76];
y = [-16.55;-16.55;-16.55;-16.62;-16.69;-16.69;-25.44;-34.19;-51.69;-51.69;-42.98;-42.98;-51.73;-60.48;-69.23;-70.48;-71.73;-81.73;-104.23;-126.73;-149.23;-149.23];
pgon = polybuffer([x y],'lines',2);
plot(pgon,'FaceColor','r','FaceAlpha',1,'EdgeColor','none')
% plot(x,y)

Accepted Answer

Jonas
Jonas on 21 Dec 2022
x = [-27.59;-32.36;-32.36;-24.99;-25.12;-32.62;-37.62;-42.62;-37.62;-37.62;-40.11;-40.11;-37.61;-33.36;-29.11;-27.11;-25.11;-20.61;-14.36;15.64;45.64;158.76];
y = [-16.55;-16.55;-16.55;-16.62;-16.69;-16.69;-25.44;-34.19;-51.69;-51.69;-42.98;-42.98;-51.73;-60.48;-69.23;-70.48;-71.73;-81.73;-104.23;-126.73;-149.23;-149.23];
subplot(1,2,1);
scatter(x,y,'ko')
hold on;
% you can try to use a sgolay filter directly on the data
smoothx=smooth(x,'sgolay');
smoothy=smooth(y,'sgolay');
plot(smoothx, smoothy)
dx=diff(x);
dy=diff(y);
factor=5;
interpx=cumsum([x(1); repelem(dx/factor,factor)]);
interpy=cumsum([y(1); repelem(dy/factor,factor)]);
% or you do some interpolation before to generate more point and change the
% parameters of the smooth function as needed
smoothx=smooth(interpx,15,'sgolay',2);
smoothy=smooth(interpy,15,'sgolay',2);
subplot(1,2,2)
scatter(x,y,'ko')
hold on;
scatter(interpx,interpy,'r.');
plot(smoothx, smoothy)
linkaxes()
  1 Comment
Smithy
Smithy on 21 Dec 2022
Wow, Thank you very much. It works really well. I really really appreciate with it.

Sign in to comment.

More Answers (0)

Tags

Products


Release

R2022a

Community Treasure Hunt

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

Start Hunting!