%
%   SF_DEMO4_EQN.M   Function file for SF_DEMO4.M
%
%   This file simply evaluates yp = f(x,y) for the input x and y values.
%   Called as part of solution for plotting slope fields.
%
%   File prepared by J. R. White, UMass-Lowell (Feb. 2005)
%
      function yp = eqnfile(x,y)
      yp = y./x;
%
%   Note: If this function is evaluated at x = 0, we will get a divide by zero
%     error.  In general, this is a situation you want to avoid.  However, Matlab
%     usually handles this condition rather gracefully, so we won't worry about  
%     this at the current time...
%
%   end of function