Fit a line to data using regress

4 次查看(过去 30 天)
Hey all, I am trying to use a new matlab function "regress" and would like some help on how to use it to fit a line.
below is my code that I have so far, but lost on how to use the "regress" function.
x = 0:0.1:10;
n = 0;
noise = n*rand(1,length(x));
y = 2*x+1+noise;
figure(1);
plot(x,y,'d')

回答(1 个)

Adam Danz
Adam Danz 2020-9-25
编辑:Adam Danz 2020-9-25
  2 个评论
Nicholas Deosaran
Nicholas Deosaran 2020-9-25
Oh okay, I see.
and to plot that line on the axis..will it be
x = 0:0.1:10;
n = 0;
noise = n*rand(1,length(x));
y = 2*x+1+noise;
b = regress(y(:),x(:));
plot(x,y,'d') %plot as diamonds
hold on
plot(b,y)
hold off
is that correct?
Adam Danz
Adam Danz 2020-9-25
编辑:Adam Danz 2020-9-28
No, b is just the slope if you've used the syntax from my answer.
If you want to plot the regression line you'll need the y-intercept term. To get the y-intercept term you need to add a column of 1s to x.
b = regress(y(:),[ones(size(x(:))),x(:)]);
b is a 2x1 vector containing the [intercept; slope];
Use refline(b(2),b(1)) to add the regression line.
Or, check out lsline.
Or, check out polyfit(x,y,1) along with refline.

请先登录,再进行评论。

Community Treasure Hunt

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

Start Hunting!

Translated by