how to plot forward difference error against h values ?

% Here is the code which I wrote but I'm not sure about. I think there are errors and I dont understand the last part which says use a function thanks for helping.

a=1;
h=10.^[-1:-1:-10];
x=a;
tval=(1/x)-1
%Forward
x=a+h;
f1=2-x+log(x);
x=a;
f2=2-x+log(x);
f3=(f1-f2)./h
Eabs=abs(tval-f3)
plot(Eabs,h)

Answer 1

[Dyuman Joshi]

So when you save what you have written in a file, that would be saved as a script file. You have to manually update different values for different results and run them each time.

Difference between script and function

So, for a function file you have to define the syntax, as mentioned in the web page above.

function output = function_name(input)
your_code...
end

and then you can get outputs by calling the file without running it manually.