why matlab is not calculating erfc?

I am writing a code requiring matlab to calculate something. Matlab is showing me answer as function of erfc. I can put the answer in a seperate editor file to calculate it. Why MATLAB is not calculating erfc directly itself. My code is

deltaH = 2;

x = 100;

l = 300;

p = 2;

omea= x/l;

deltat = 5;

v = 140;

syms m

u = x/sqrt(v*deltat);

erfun = erfc(u/2*sqrt(p-m));

tek = deltaH*erfun;

summ = symsum(tek,m,1,p)

I am getting answer as 2*erfc((5*7^(1/2))/7) + 2 which can be evaluated but I want MATLAB to give me answer as a number.

Answer 1

[Star Strider]

I did not run your code, but if you want a numerical answer change the ‘summ’ line to:

summ = vpa(symsum(tek,m,1,p))