Calculating young's modulus from stress strain curve

I am currently using approximately 13000 data points of both stress and strain and I have managed to plot the graph. Now I need to calculate the young's modulus. I know it is possible to just take 2 points and calculate it as a linear function, but the answer differs a bit too much depending on what points that are chosen. I would like to calculate some kind of value using all the data points from 10% of the strain to 40% of the strain to get a better result. Help is much appreciated, if more information is needed I am more than happy to send more

Answer 1

[Stephan]

Hi,

since this is a linear problem the best and most elegant way to solve this is mldivide. This will solve your problem in a least squares sense, which means that the calculated value represents the best linear fit.

Best regards

Stephan