How to call a function to another m file?

My goal is to create a script m-file to plot temperature vs resitivity as described by 2 equations on the same axis. I have been informed to code equations 1 and 2 in 2 seperate functions which I have done (resitiviity and resitivity2). I am trying to call them in another m file called tempvres. However when I execute the code I am gaining a blank graph which isn't what im trying to obtain.

Resitivity function ^

Resitivity2 function ^

tempvres script ^

An example output when I type 100 in as the temp difference.

Answer 1

[Image Analyst]

temp and r2 are probably scalars not vectors.