Errorbar Plot with Line of best fit

Sorry for a basic question, I am trying to add a line of best fit to an error plot in the following manner, (just an examples)

x = [1 2 3 4];
y = [2 4 6 8];
yneg =[0.5 0.5 0.5 0.5];
ypos =[0.5 0.5 0.5 0.5];
xpos = [0.1 0.1 0.1 0.1];
xneg = [0.1 0.1 0.1 0.1];

errorbar(x,y,yneg,ypos,xneg,xpos,'bo')

I have tried

lsline

But this hasn't worked can anyone advise me on how to resolve this?

Answer 1

[Star Strider]

Try this:

x = [1 2 3 4];
y = [2 4 6 8];
yneg =[0.5 0.5 0.5 0.5];
ypos =[0.5 0.5 0.5 0.5];
xpos = [0.1 0.1 0.1 0.1];
xneg = [0.1 0.1 0.1 0.1];

B = [x(:) ones(size(x(:)))] \ y(:);
yfit = [x(:) ones(size(x(:)))]  * B;

figure
errorbar(x,y,yneg,ypos,xneg,xpos,'bo')
hold on
plot(x, yfit, '-r')
hold off

I believe lsline only works with scatter plots.

EDIT —

Added plot figure —

Answer 2

[dpb]

S-S is correct that per the documentation lsline only works for scatter plots or not connected lines with plot

Perhaps just a little more intuitive

b=polyfit(x,y,1);  % use polyfit for coefficients rather than backslash
refline(b)         % will work when give the coefficients explicitly

Looks like a "quality of implementation" issue to me that lsline can't find the unconnected line in an errorbar object. Probably worth an enhancement request, or at least Tip in documentation.