%
%   PSeries_Ex1a.m  Function evaluation for ODE step 
%                    in Matlab file PSeries_Ex1.m
%     
%   ODE:  (x^2 - 4)y'' + 3xy' + y = 0
%
%   File prepared by J.R. White, UMass-Lowell (Oct. 2003).
%
      function zp = odefile(x,z)
      zp = zeros(length(z),1);
      zp(1) = z(2);
      zp(2) = -(3*x*z(2) + z(1))/(x*x-4);
%
%   end of function

