function out=salfunc(zsr,p);
Co=34.6783;
Cm=34.3859;
Zm=2023.6;
out = Co+(Cm-Co)*[(exp(zsr/p(1))-1)/(exp(Zm/p(1))-1)];
%out = Co+(Cm-p(1))*[(exp(zsr/p(2))-1)/(exp(Zm/p(2))-1)];