Available with 3D Analyst license.
The ability to produce statistical information for LAS files referenced by the LAS dataset is essential to better understand the lidar and point cloud data that you are working with in ArcGIS Pro. Statistical analysis allows you to conduct initial quality assurance and quality control on lidar data to ensure that the data deliverables are exactly what was expected. It also allows you to determine the overall quality and extent of the data prior to conducting time-consuming processes on the lidar data.
When statistics are calculated, a LAS auxiliary file (.lasx) is created for each LAS file. The auxiliary file (.lasx) is given the same name as the source LAS file and stored in the same location on disk. It stores the calculated statistical information and the spatial index for each LAS file. If statistics were not generated using the Create LAS Dataset tool, use the LAS Dataset Statistics tool to calculate statistics. If LAS files that are added to a LAS dataset already contain a LAS auxiliary file (.lasx), statistics have already been calculated and will not need to be recalculated.
Statistics can be computed for an entire LAS dataset containing several LAS files, or they can be computed for a single file.
Note:
Point spacing is not the same as point density. Point spacing (PS) is defined as linear units per point, and point density (PD) is defined as points per square unit area. To convert point spacing to point density, use the following equation: PD = 1/(PS)^2. A higher point density means lower values for point spacing.
Generate statistics on a LAS dataset
Statistics can be generated and updated in several ways for the LAS dataset. You can use any of the following methods to calculate statistics on your LAS dataset:
- Create LAS Dataset geoprocessing tool
- LAS Dataset Statistics geoprocessing tool
- LAS Dataset Properties dialog box from the Catalog pane
Create LAS Dataset geoprocessing tool
The Create LAS Dataset tool builds a LAS dataset referencing LAS files by scanning the header information of the LAS files. It will optionally scan through the lidar files referenced by the LAS dataset and calculate statistics about each LAS file individually, as well as the collection of LAS files. The results can be reviewed through the LAS Dataset Properties window in the Catalog window.
To generate statistics using the Create LAS Dataset tool, check the Compute Statistics parameter prior to executing the tool.
Note:
Calculating statistics requires a complete scan of the referenced LAS files. The time it takes to compute statistics will correspond to the number of points in the LAS files, but will yield much more information. Gathering statistics is recommended if you are not in a time-critical situation. Keep in mind that statistics can always be calculated at a later time using either the LAS Dataset Statistics tool or the LAS Dataset Properties dialog box.
LAS Dataset Statistics geoprocessing tool
The LAS Dataset Statistics tool generates statistics for LAS datasets and optionally outputs the statistical analysis to a text file. The tool generates an output report that can then be loaded into a spreadsheet or database program. The tool scans through the lidar files referenced by the LAS dataset and calculates statistics about each LAS file individually, as well as the collection of LAS files.
If statistics were not generated using the Create LAS Dataset tool, use the LAS Dataset Statistics tool to calculate statistics.
The results can be reviewed through the LAS Dataset Properties window in the Catalog pane.
Catalog pane
The LAS Dataset Properties dialog box from the Catalog pane also allows you to calculate or update statistical information for the LAS dataset. This dialog box reports information about the LAS dataset as a whole, plus details about the specific LAS files that participate in the dataset.
If statistics were not generated using either the Create LAS Dataset or the LAS Dataset Statistics tool, you can calculate statistics interactively for a LAS dataset or individual LAS file using the LAS Dataset Properties dialog box.
The statistical results can be reviewed immediately for the LAS dataset through the Statistics tab of the LAS Dataset Properties dialog box. For individual LAS files, the statistics can be reviewed by clicking the Details button for that LAS file located on the LAS Files tab. The LAS Dataset Properties dialog box cannot be used to export the statistics to a text file; use the LAS Dataset Statistics tool to create an output report.
- Right-click the LAS dataset icon
in the Catalog pane and click Properties. - Click the Statistics tab on the LAS Dataset Properties dialog box.
- If the LAS dataset has not had statistics calculated, click the Update button to calculate statistics. If the LAS dataset has already had statistics calculated, click the Update button to update statistics. This button is unavailable if statistics are up to date.
Note:
The Update button computes statistics for the first time or recomputes statistics if they are out of date as a result of editing.
Generate statistics on a single LAS file
The LAS Dataset Properties dialog box reports information about the LAS files that participate in the LAS dataset. Follow the steps below to calculate statistics for a single LAS file referenced by the LAS dataset.
- Right-click the LAS dataset icon in the Catalog pane and click Properties.
- Click the LAS Files tab on the LAS Dataset Properties dialog box.
- From the list of LAS files, click the button under the Details column that corresponds to the LAS file for which statistics will be generated.
- From the dialog box, click the Update button to calculate the statistics for the specific LAS file.
Note:
The Update button computes statistics for the first time or recomputes statistics if they are out of date. You can also use the arrow buttons to see another LAS file referenced by the LAS dataset to compute statistics for another file.