function nu = pma(m,gamma)
%pma         This function computes the Prandtl-Meyer
%            angle (degrees) that coresponds to a given 
%            mach no.  & gamma.  The form is:
%            [mach no.] = pmm (nu, gamma)
%            (note: m and gamma should be scalars)

expn = atan((m^2-1)^.5);
rat=(gamma+1)/(gamma-1);
g = (rat^.5)*atan((((gamma-1)/(gamma+1))*...
          (m^2-1))^.5)-expn;

nu=180/pi*g;

