unexpected matlab expression during hdl code generation

Dear sir/madam, whenever I am trying to generate a verilog code I am getting an 'Unexpected Matlab Expression' error.. I googled the solution, but I am unable to understand what's wrong... plz help.. Here's my code

function y = fir_project(x,h)
% x = [1/5,2/5,3/5,4/5];
% h = [1/3,1/3,1/3];
% initialize
x1 = 0;
x2 = 0;
y = zeros(1,length(x));
for k = 1:length(x)

      if k-2 == -1 || k-2 == 0
          x2 = 0;
      else
          x2 = x1;
      end

      if k-1 == 0
          x1 = 0;
      else
          x1 = x(k-1);
      end
      y(k) = (h(1)*x(k))+(h(2)*x1)+(h(3)*x2);
  end

end

The x and h values are given in comments. Thanks in advance. This is the error I am getting

   emlhdlcoder.WorkFlow.Manager.instance.wfa_generateCode(' C:\Documents 
\matlab\fir's project\firproj2.prj ');
                                                                                   |
  Error: Unexpected MATLAB expression.

Answer 1

[Tim McBrayer]

I think that HDL Coder will have a hard time with your variable loop bound; this is hard to build hardware for. I have no issues when I use a constant 4 instead of the expression length(x) .