Curve fitting... Matrix dimensions do not agree

I need to fit the non-linear data to the curve and use polyfit to obtain Ea and A. I believe I have Ea = 35.42. I'm super tired can someone please explain what I am doing wrong here? The matrix dimensions do not agree and I am having a hard time seeing the variable dimensions in my gui.

function prob3()
close all
T = [773 786 797 810 810 820 834];
K = [1.63 2.95 4.19 8.13 8.19 14.9 22.2];
R = 8314;
% Your work goes here ...
figure
plot(T,K,'k.','markersize',50);
daspect([1 1 1])
set(gca,'fontsize',18);
axis([770 840 0 50]);
set(gca,'dataaspectratiomode','auto');
% k = Aexp(-Ea/RT)
% log(k) = log(A) + log(exp(-Ea/RT))
acoeffs = polyfit(log(T), log(K),1)
A = exp(acoeffs(2))
Ea = acoeffs(1)
xl = linspace(770, 10, 840);
kl = A.*exp(Ea.*xl./R.*T);
hold on
figure
plot(xl,kl,'r')
% Be sure to include : 
%   -- Plots of data points
%   -- Best fit curve to your datat
%   -- axis labels
%   -- title 
%   -- Legend. 
write_file([A,Ea],'reactioncoeffs.out');
end

Answer 1

[KSSV]

Lengths of xl and T should be same for multiplication.

Replace line:

xl = linspace(770, 10, 840);

with

xl = linspace(770, 10, length(T));