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| ArcObjects namespaces > Geometry > ESRI.ArcGIS.Geometry > Interfaces > IF > IFunctionalSurface Interface > IFunctionalSurface.Z Property (ArcObjects .NET 10.4 SDK) | 
The surface Z=f(x,y).
[Visual Basic .NET] Public Function get_Z ( _ ByVal X As Double, _ ByVal Y As Double _ ) As Double
[C#] public double get_Z ( double X, double Y );
[C++]
HRESULT get_Z(
  double X,
  double Y,
  double* Z
);
[C++]
Parameters X X is a parameter of type double Y Y is a parameter of type double Z [out, retval] Z is a parameter of type double
Returns the Z value for the (x, y) coordinate on the FunctionalSurface. If the (x, y) coordinate is outside of the Domain for which the FunctionalSurface is defined, a NaN is returned.