
plot3dc: Magnitude colored plot surface with contour 

DESCRIPTION:

    This function is used in example 21. 

SYNOPSIS:

plot3dc(x, y, z, nx, ny, opt, clevel, nlevel)

ARGUMENTS:

    x (const PLFLT *, input) :      Pointer to set of x coordinate values at
    which the function is evaluated. 

    y (const PLFLT *, input) :      Pointer to set of y coordinate values at
    which the function is evaluated. 

    z (const PLFLT * const *, input) :      Pointer to a vectored
    two-dimensional array with set of function values. 

    nx (PLINT, input) :    Number of x values at which function is
    evaluated. 

    ny (PLINT, input) :    Number of y values at which function is
    evaluated. 

    opt (PLINT, input) :    Determines the way in which the surface is
    represented. To specify more than one option just add the options,
    e.g. DRAW_LINEXY + MAG_COLOR opt=DRAW_LINEX: Lines are drawn
    showing z as a function of x for each value of y[j]. 
        opt=DRAW_LINEY: Lines are drawn showing z as a function of y
        for each value of x[i]. 
        opt=DRAW_LINEXY: Network of lines is drawn connecting points
        at which function is defined. 
        opt=MAG_COLOR: Each line in the mesh is colored according to
        the z value being plotted. The color is used from the current
        color map 1. 
        opt=BASE_CONT: A contour plot is drawn at the base XY plane
        using parameters 
    nlevel and 
    clevel. 
        opt=DRAW_SIDES: draws a curtain between the base XY plane and
        the borders of the plotted function. 


    clevel (const PLFLT *, input) :    Pointer to the array that defines
    the contour level spacing. 

    nlevel (PLINT, input) :    Number of elements in the clevel array. 
