help surface
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Title

   Produce a Wireframe Surface plot

Syntax

        surface [var1 var2 var3] [, options]

    options               Description
    -------------------------------------------------------------------------
    Main
      saving(filename[, replace ])
                            saves the graph to a specified file name.
      round(#)             specifies the precision of the x and y variables
                            so that a wireframe can be drawn.
      labelround(#)        specifies the precision of the x, y and z
                            automatic axes labels.
      orient(string)       specifies which axes should be the x, y and
                            z-axes.
      nowire               specifies that the data is plotted as a point and
                            a dropline.
      xtitle(string)       specifies the title for the x-axis.
      ytitle(string)       specifies the title for the y-axis.
      ztitle(string)       specifies the title for the z-axis.
      xlabel(numlist)      specifies the labelling on the x-axis.
      ylabel(numlist)      specifies the labelling on the y-axis.
      zlabel(numlist)      specifies the labelling on the z-axis.
    -------------------------------------------------------------------------


Description

    The function attempts to draw a wireframe plot from three variables.
    Var1 specifies the x-coordinate, var2 the y-coordinate and var3 the
    z-coordinate. Alternatively the function can draw a circle at each point
    and add a straight line going down to the lowest point.

    This function can handle data that is not in the form of a matrix of
    values.  However if there are too many x- and y- values the function will
    attempt to round the dataset values into a more reasonable spread of
    values. This will result in very messy figures. However in such a case it
    is the impression that is needed. Many other statistical packages require
    a full matrix of values. This is not a problem using the nowire option.

    At present the state of rotating the diagram is limited to interchanging
    the axes.

Options

    saving(filename [, replace ]) this will save the resulting graph in
        filename.gph. If the file already exists then use the replace
        suboption.

    nowire this suppresses the drawing of the wire frame in exchange for
        lines

    round(#), data is automatically rounded if there are too many x and y
        values. This option controls the amount of rounding, for example
        round(1) rounds the x and y values to the nearest integer.

    labelround(#) specifies the precision of the x, y and z automatic axes
        labels.

    orient(string ) this function must take the letters xyz or a combination
        of them. Whichever letter comes first is the x-axis, second is y-axis
        and third is the z-axis. Thus orient(zxy) means that var1 is now the
        y coordinates, var2 is the z-coordinates and var3 is the
        x-coordinates. This is different from changing the variables around
        since the wireframe is still draw across the original x and y values.
        This is a crude attempt to implement rotation to obtain a clearer
        picture.

    xtitle(string) specifies the title for the X-axis, the default is
        "X-axis"

    ytitle(string) specifies the title for the Y-axis, the default is
        "Y-axis"

    ztitle(string) specifies the title for the Z-axis, the default is
        "Z-axis"

    xlabel(numlist) specifies the labelling on the X-axis.

    ylabel(numlist) specifies the labelling on the Y-axis.

    zlabel(numlist) specifies the labelling on the Z-axis.

Examples

    surface x y z, saving(myfile) round(10) orient(zxy)

    surface x y z, xtitle(my x title) ytitle(my y title) ztitle(my z title)
        saving(myfile,replace)

    An "immediate" example without using a dataset. Please click the commands
    in order to avoid problems.

    clear <--- NOTE all data is removed you may want to preserve first
    set obs 900
    gen x = int((_n - mod(_n-1,30) -1 ) /30 )
    gen y = mod(_n-1,30)
    gen z = normalden(x,10,3)*normalden(y,15,5)
    surface x y z
    surface x y z, zlabel(0 0.005 0.012) labelround(1) xtitle(X-variable)

Author

    Adrian Mander, MRC Biostatistics Unit, Cambridge, UK.

    Email adrian.mander@mrc-bsu.cam.ac.uk

See Also

    Other Graphic Commands I have written:

    batplot (if installed)        ssc install batplot (to install)
    cdfplot (if installed)        ssc install cdfplot (to install)
    contour (if installed)        ssc install contour (to install)
    drarea (if installed)         ssc install drarea (to install)
    graphbinary (if installed)    ssc install graphbinary (to install)
    metagraph (if installed)      ssc install metagraph (to install)
    palette_all (if installed)    ssc install palette_all (to install)
    plotbeta (if installed)       ssc install plotbeta (to install)
    plotmatrix (if installed)     ssc install plotmatrix (to install)
    radar (if installed)          ssc install radar (to install)
    trellis (if installed)        ssc install trellis (to install)