time   calls  line
                  1 function c = cross(a,b,dim)
                  2 %CROSS  Vector cross product.
                  3 %   C = CROSS(A,B) returns the cross product of the vectors
                  4 %   A and B.  That is, C = A x B.  A and B must be 3 element
                  5 %   vectors.
                  6 %
                  7 %   C = CROSS(A,B) returns the cross product of A and B along the
                  8 %   first dimension of length 3.
                  9 %
                 10 %   C = CROSS(A,B,DIM), where A and B are N-D arrays, returns the cross
                 11 %   product of vectors in the dimension DIM of A and B. A and B must
                 12 %   have the same size, and both SIZE(A,DIM) and SIZE(B,DIM) must be 3.
                 13 %
                 14 %   Class support for inputs A,B:
                 15 %      float: double, single
                 16 %
                 17 %   See also DOT.
                 18 
                 19 %   Copyright 1984-2010 The MathWorks, Inc.
                 20 %   $Revision: 5.18.4.5 $  $Date: 2010/08/23 23:13:01 $
                 21 
                 22 % Special case: A and B are vectors
             5   23 rowvec = 0; 
             5   24 if ismatrix(a) && ismatrix(b) && nargin<3 
             5   25     if size(a,1)==1, a = a(:); rowvec = 1; end 
             5   26     if size(b,1)==1, b = b(:); rowvec = 1; end 
             5   27 end; 
                 28 
                 29 % Check dimensions
  0.01       5   30 if ~isequal(size(a),size(b)), 
                 31    error(message('MATLAB:cross:InputSizeMismatch'));
                 32 end
                 33 
             5   34 if nargin == 2 
             5   35    dim = find(size(a)==3,1); 
             5   36    if isempty(dim),  
                 37      error(message('MATLAB:cross:InvalidDimAorB'));
                 38    end
             5   39 end; 
                 40 
                 41 % Check dimensions
             5   42 if (size(a,dim)~=3) || (size(b,dim)~=3), 
                 43   error(message('MATLAB:cross:InvalidDimAorBForCrossProd'))
                 44 end
                 45 
                 46 % Permute so that DIM becomes the row dimension
             5   47 perm = [dim:max(length(size(a)),dim) 1:dim-1]; 
             5   48 a = permute(a,perm); 
             5   49 b = permute(b,perm); 
                 50 
                 51 % Calculate cross product
             5   52 c = [a(2,:).*b(3,:)-a(3,:).*b(2,:) 
                 53      a(3,:).*b(1,:)-a(1,:).*b(3,:)
                 54      a(1,:).*b(2,:)-a(2,:).*b(1,:)];
             5   55 c = reshape(c,size(a)); 
                 56 
                 57 % Post-process.
             5   58 c = ipermute(c,perm); 
             5   59 if rowvec, c = c.'; end