clear all
 
  h = 2/100;
  L = input('L = ');
  for i = 1:101
    x = -1 + i*h;
    X(i) = x;
    for j = 1:101;
      y = -1 + j*h;
      Y(i) = y;
      C(i,j) = exp(-abs(x-y)/L)/(2*L);
    end
  end
 
  mesh(C)  
  pause
  close all

%
%  Better way to program the function.
%

  [X,Y] = meshgrid(-1:.02:1);
  C = exp(-abs(X-Y)/L)/(2*L);

  mesh(X,Y,C)