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Topic: **How to write a program in matlab****Question:**
I am fitting a 2nd order regression curve to some data ussing a least squares method and finding the required co-efficents, m-file polyregr2.m which works fine...
Now I'm trying to visualise this fit ussing with a second m-file (plotreg.m) wich I want to pull all the data from polyregr2.m to complete the m-file file I wrote is shown;
polyregr2(T,v);
t = min(T):0.05:max(T);
m = size(t,2);
for i = 1:m
f(i) = a(n+1);
for j = n:-1:1;
f(i) = a(j) + f(i)*t(i);
end
end
plot(t,f,'r--')
hold on
plot(v, T, 's')
Now when I put all this in an error saying I haven't defined any of the co-efficents comes up when it should have got it from poleregr2.m how can I make this happen?
In polyreg2r.m I have defined T,v and n

June 27, 2019 / By Orson

u call polyregr2(T,v); whitout giving values to T and v edit doesnt poluregr2 needs a input for work? if no give it some outputs and do [T v n]=poliregr2; poliregr2 need to have a output in the *.m file note every time u get out of a function it reset all the variables (unless they are global or they are returned)

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