Hi
I have a problem with extending my polyfit line. I tried to extend it by changing "T" for polyval (which is temperature and x-axis) to contain the whole dataset for temperature to get an extended line ranging the whole plot. I wanted a line that was extended like 4 degrees celsius, but wanted to checking if it worked by including the whole data set first. It did not. All the y-values decreased and the extended line does not look linear any more.
Should this solution work, and if so what have I done wrong?
Is there another solution to extend the line?
Thanks a lot for the help
% Getting index for temperature values
[d,posmin] = min(abs(x11-0));[d,negmax] = min(x11-10);x111 = x11(negmax:lastrow11);[d,negmin1] = min(abs(x111-0));negmin = negmax+negmin1-1;% Getting x and y values
T11 = x11(1:posmin); A11 = y11(1:posmin);T12 = x11(posmin:negmax); A12 = y11(posmin:negmax);T13 = x11(negmax:negmin); A13 = y11(negmax:negmin);T14 = x11(negmin:lastrow11); A14 = y11(negmin:lastrow11);% Fitting values
[p11,s11] = polyfit(T11,A11,1);f11 = polyval(p11,wholedataset);[p12,s12] = polyfit(T12,A12,1);f12 = polyval(p12,T12);[p13,s13] = polyfit(T13,A13,1);f13 = polyval(p13,T13);[p14,s14] = polyfit(T14,A14,1);f14 = polyval(p14,T14);
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