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The G3GRID Procedure |

- create a rectangular grid of interpolated or smoothed
values from irregularly spaced observations for use in a three-dimensional
surface or contour plot
- complete a rectangular grid of interpolated or
smoothed values for an input data set that has an insufficient number of observations
to produce a three-dimensional surface or contour plot
- interpolate or smooth noisy data for a three-dimensional
graph.

The G3GRID procedure does not produce graphics output. Instead, it produces an output data set that you can use as the input data set for the G3D or GCONTOUR procedure.

Scatter Plot of Data Set before G3GRID Processing (GR30N01(a)) and Surface Plot of Data Set after G3GRID Processing (GR30N01(b)) illustrate the effect of the G3GRID procedure on data.

Scatter Plot of Data Set before G3GRID Processing (GR30N01(a))
shows a collection of data points, where **z**=**f**(**x**, **y**). These points are randomly distributed and cannot
be displayed with a G3D surface plot, although they can be displayed with
a scatter plot.

*Scatter Plot of Data Set before G3GRID Processing (GR30N01(a))*

Surface Plot of Data Set after G3GRID Processing (GR30N01(b)) shows a surface plot of the data set that is created by a G3GRID interpolation of the original data set shown in Scatter Plot of Data Set before G3GRID Processing (GR30N01(a)).

*Surface Plot of Data Set after G3GRID Processing (GR30N01(b))*

**Note:** The evenly distributed horizontal (**x**, **y**) data points form a grid for the three-dimensional
graph.

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