MATLAB: Help with “While” loop, not sure what I’m doing

while loop

I have started learning to use Matlab, I have a program that a colleague of mine has written for processing my data and I can't figure out why some of the script is not working. In the following loop, the first equation (RHlsun) uses the original value of glsuni istead of the new value from the loop. I hope this makes sense. What am I doing wrong?
counter = 0;
glsuni = 0.5;
glsun = 0.0;
converge1 = abs(glsuni - glsun);
while converge1>0.0005;
RHlsun = 1 - (1 - (RH / 100)) .* (((2 * glsuni * ((fgreen * fdry) / fstomata)) .* gvl .* (gbc ./ LAIsun)) ./ ((2 * glsuni .* ((fgreen * fdry) / fstomata)) .* ((2 * glsuni .* ((fgreen * fdry) / fstomata)) .* gvl + (2 * glsuni .* ((fgreen * fdry) / fstomata)) .* (gbc ./ LAIsun) + gvl .* (gbc ./ LAIsun))));
sRHlsun = (sqrt((RHlsun.^2) + (RHlmin^2))) ./ (sqrt(1 + (RHlmin^2)));
CO2lsun = CO2i - (CO2i - CO2a) * (((2 * 0.625 * glsuni * ((fgreen * fdry) / fstomata)) .* gcl .* (gbc ./ LAIsun)) ./ ((2 * 0.625 * glsuni * ((fgreen * fdry) / fstomata)) .* ((2 * 0.625 * glsuni .* ((fgreen * fdry) / fstomata)) .* gcl + (2 * 0.625 * glsuni * ((fgreen * fdry) / fstomata)) .* (gbc ./ LAIsun) + gcl .* (gbc ./ LAIsun))));
glsun = mBWB .* ((Ansun .* sRHlsun) ./ CO2lsun) + bBWB;
counter = counter + 1;
converge1 = abs(glsuni - glsun);
glsuni = glsun;
if counter > 30;
break;
end;
end;

Best Answer

Start with a simplification of the code:
counter = 0;
glsuni = 0.5;
glsun = 0.0;
converge = abs(glsuni - glsun);
c1 = (fgreen * fdry) / fstomata;
c4 = gbc ./ LAIsun;
while converge > 0.0005 || counter > 30
c2 = 2 * glsuni * c1;
c3 = c2 * 0.625;
RHlsun = 1 - (1 - (RH / 100)) ./ (c2 ./ c4 + c2 ./ gvl + 1);
sRHlsun = sqrt(RHlsun .^ 2 + RHlmin ^ 2) ./ sqrt(1 + RHlmin ^ 2);
CO2lsun = CO2i - (CO2i - CO2a) ./ (c3 ./ c4 + c3 ./ gcl + 1);
glsun = mBWB .* Ansun .* sRHlsun ./ CO2lsun + bBWB;
converge = abs(glsuni - glsun);
glsuni = glsun;
counter = counter + 1;
end
Perhaps this allows you to see the problem by your own.