Help with basic fitting

Hello,I would like to fit a curve with a line and retrieve slope and intercept of this linear fit. Let x and y be the vectors which define the curve, which is already similar to a line; I plot x vs y, then from the plot window I select Tools --> Basic fitting --> Linear fit, then I press 'Show equation' so that from the expression y=mx + q I retrieve both the slope m and the intercept q. The problem is that I want to obtain immediatly m and q from the Matlab code, without doing it manually as discussed above. How can I do this ? Thanks

Answer 1

[Mischa Kim]

Try

 [p,S] = polyfit(x,y,1)

The two elements of p are the coefficients m and q you are looking for.

[Andrea Gómez Montoya]

What is S on the answer?

[Image Analyst]

It's explained in the help for polyfit().

Answer 2

[Image Analyst]

for what it's worth, I've attached a demo of polyfit.