Using arrays and finding the slope

Would it be appropriate to use this kind of logic in Matlab? I am getting a weird slope graph so I wanted to double check.

From this graph ex:

plot(strainpercentage(452:502),c3(452:502))

To find the slope, this plot:

plot(c3(452:502)./strainpercentage(452:502))

Answer 1

[Jan]

Use gradient of diff to determine the slope.

plot(diff(c3(452:502))./diff(strainpercentage(452:502)))

[Christine Nee]

Great, that makes more sense. Thanks