Computing Different Z Values by Vertex

About calculating one Z value for each vertex for the input geometry

Calculating Z values for each vertex computes a single value for each vertex in the input geometry. This option probes into the points using either the points themselves or a TIN (for the Surface Z option) and creates an independent Z value for each existing vertex on the line. The Z value does not get stored in the Attribute table of the feature for this option.

The Z value is determined based on the Z Value you choose in the Summarize Z Values dialog box.

• Mean Z - The Z value is summarized within a range.
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• Minimum Z, Maximum Z, and Closest Z - All of the points within this distance are involved in the requisite computation on a per vertex basis.
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  Note   Mean, Minimum, or Maximum values are defined by selecting a spatial relationship between the input geometry and the LAS points. Learn more about selecting a spatial relationship.

• Surface Z - This is the TIN Surface elevation from the LAS points and is essentially a drape of the TIN.
  
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• Constant Z - You can assign an elevation by keying in a specific value.

This method of Z computation is generally useful for creating Z values that are off the TIN, which is what distinguishes this method from the Drape method.

Since this method stores Z on the vertex feature, it must have a 3D feature file. The feature file can include Measure ("M") values on the vertices but they will not be used.

Learn more about the Summarize Z Values dialog and the other Summarize Z Conflation options

Example of using the "by vertex" option

Surface Z calculated for each vertex of the input geometry

How to Open the Summarize Z Values Dialog

The Calculate Z by Vertex option is selected on the Summarize Z Values dialog box. There are three situations in which you will encounter this dialog:

(1) When setting up an elevation conflation task, you begin by using the Elevation Conflation/Classify dialog box, opened using the  button on the LP360 Classify toolbar. Once you select the Layer or Data Set and then the features (in the Fields drop-down) to use to use in the conflation, you will select a Conflation Method for each listed feature in the Data Types table.

To select the conflation method, click on the cell under Conflation Method in the table next to one of the listed features. Another drop-down list will allow you to select a conflation method.

 Select Summarize Z. The Summarize Z Values dialog will open.

 

(2)  When digitizing features in LP360, you will likely have the LP360 Digitize Breaklines toolbar open, and from this, you can manage conflation tasks using the Conflate Tasks Manager. (It opens using the button on the LP360 Digitize Breaklines toolbar.)

When you select a task in the Conflate Tasks Manager dialog box and then click the Edit Task button, the LP360 Conflate Task Dialog opens, allowing you to further define a conflation task, including the Conflation Method.

In the Conflation Method drop-down, select Summarize Z and then click the button. The Summarize Z Values dialog will open.

(3) When selecting "Summarize Z Values" from the Conflation Method drop-down list in the Conflation Point Cloud Task property page.

 

How to Calculate Z by Vertex

1. Open the Summarize Z Values dialog box, as explained in the "How to Open the Summarize Z Values Dialog" section above.
   
2. To calculate a summarized Z value and store the value in the Attribute table, select the computing one z value for each vertex for the input geometry option button.
   
   
   
3. Next, select a Z value to calculate by feature.
   
   
4. If you use the Mean, Minimum, or Maximum value to calculate Z, you will also need to select a spatial relationship. See Selecting a Spatial Relationship for more information.
   
   
5. Enter a No Data Value assignment for features or vertices that cannot be assigned a Z value. See Assigning a No Data Value for more information.
   
   
6. Click OK.