Slope of the linear(elastic) part of a stress-strain curve

So, I have a stress-strain curve. I need to find the slope of the linear part of the curve (a.k.a. Young's modulus) which is the region between the black lines.

I usually do this on Excel by drawing a trendline over this set of datapoints. How can this be done on Matlab ?

I would also need to do some corrections to the curves.

Answer 1

[Star Strider]

See: How do I determine the linear part of a force-displacement curve?

Answer 2

[KSSV]

Pick the required points (x,y) which fall in linear region.

p = polyfit(x,y,1) ; 
m = p(1)