SpatialFilter
The SpatialFilter method is used to spatially filter X, Y and Z coordinates in the worksheet. This can be useful when pre-filtering data before creating a post map, variogram, or grid file. New data are added to the bottom of the worksheet. Returns a Boolean. Returns 'True', if the process is successful, else, returns 'False'.
Syntax
object.SpatialFilter( xSourceCol, ySourceCol, zSourceCol, xTargetCol, yTargetCol, zTargetCol, ExclusionFilter, DupMethod, xDupTol, yDupTol )
|
Parameter |
Type |
Required/ Optional |
Default |
Description |
|
xSourceCol |
Long |
Required |
This specifies the X axis source column |
|
|
ySourceCol |
Long |
Required |
This specifies the Y axis source column |
|
|
zSourceCol |
Long |
Required |
This specifies the Z axis source column |
|
|
xTargetCol |
Long |
Required |
This specifies the X axis destination column |
|
|
yTargetCol |
Long |
Required |
This specifies the Y axis destination column |
|
|
zTargetCol |
Long |
Required |
This specifies the Z axis destination column |
|
|
ExclusionFilter |
Variant |
Optional |
"" |
This specifies the equation written as a string. |
|
DupMethod |
Optional |
srfDupAll |
This specifies the method for retaining duplicates. |
|
|
xDupTol |
Double |
Optional |
0.0 |
This specifies the separation distance of X values to be considered duplicates. |
|
yDupTol |
Double |
Optional |
0.0 |
This specifies the separation distance of Y values to be considered duplicates. |
Remarks
If xDupTol or yDupTol are omitted these values are assumed to be 0. This means the points must be exactly the same to be considered duplicates.
If no ExclusionFilter is specified no filtering will be preformed.
Example
This example filters points from a data file with x and y values greater than 6 units and removes all duplicates within a range of 0.5 units.
'Declares SurferApp as an object
Dim SurferApp As Object
'Creates an instance of the Surfer Application object and assigns it
'to the variable named "SurferApp"
Set SurferApp = CreateObject("Surfer.Application")
'Makes Surfer visible
SurferApp.Visible = True
'Declares Wks as an object
Dim Wks As Object
'Opens the sample Demogrid.DAT file as a worksheet document
Set Wks = SurferApp.Documents.Open(FileName:=SurferApp.Path+"\Samples\Demogrid.DAT")
'Performs the Spatial Filter operation
Wks.SpatialFilter( xSourceCol:=1 , ySourceCol:=2, zSourceCol:=3, _
xTargetCol:=4, yTargetCol:=5, zTargetCol:=6, _
ExclusionFilter:="y > 6.0 OR x > 6.0", DupMethod:=srfDupNone, _
xDupTol:=0.5, yDupTol:=0.5 )
Used by: WksDocument object