NDGRID Generation of arrays for N-D functions and interpolation.
    [X1,X2,X3,...] = NDGRID(x1,x2,x3,...) transforms the domain
    specified by vectors x1,x2,x3, etc. into arrays X1,X2,X3, etc. that
    can be used for the evaluation of functions of N variables and N-D
    interpolation.  The i-th dimension of the output array Xi are copies
    of elements of the vector xi.

MESHGRID   X and Y arrays for 3-D plots.
    [X,Y] = MESHGRID(x,y) transforms the domain specified by vectors
    x and y into arrays X and Y that can be used for the evaluation
    of functions of two variables and 3-D surface plots.
    The rows of the output array X are copies of the vector x and
    the columns of the output array Y are copies of the vector y.

    [X,Y] = MESHGRID(x) is an abbreviation for [X,Y] = MESHGRID(x,x).
    [X,Y,Z] = MESHGRID(x,y,z) produces 3-D arrays that can be used to
    evaluate functions of three variables and 3-D volumetric plots.

    For example, to evaluate the function  x*exp(-x^2-y^2) over the
    range  -2 < x < 2,  -2 < y < 2,

        [X,Y] = meshgrid(-2:.2:2, -2:.2:2);
        Z = X .* exp(-X.^2 - Y.^2);
        mesh(Z)

    MESHGRID is like NDGRID except that the order of the first two input
    and output arguments are switched (i.e., [X,Y,Z] = MESHGRID(x,y,z)
    produces the same result as [Y,X,Z] = NDGRID(y,x,z)).  Because of
    this, MESHGRID is better suited to problems in cartesian space,
    while NDGRID is better suited to N-D problems that aren't spatially
    based.  MESHGRID is also limited to 2-D or 3-D.

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