RasterStatistics Task

This task computes statistics on a raster.

Use the RasterHistogram task to compute a histogram for a raster.

Example

; Start the application

e = ENVI()

; Open an input file

File = Filepath('qb_boulder_msi', Subdir=['data'], $

Root_Dir=e.Root_Dir)

Raster = e.OpenRaster(File)

; Get the task from the catalog of ENVITasks

Task = ENVITask('RasterStatistics')

; Define inputs

Task.INPUT_RASTER = Raster

Task.OUTPUT_REPORT_URI = e.GetTemporaryFilename('txt')

; Run the task

Task.Execute

; Print Statistics

Print, Task.MAX

Print, Task.MEAN

Print, Task.MIN

Print, Task.NPIXELS

Print, Task.STDDEV

Syntax

Result = ENVITask('RasterStatistics')

Input parameters (Set, Get): COMPUTE_COVARIANCE, COMPUTE_HISTOGRAMS, INPUT_RASTER, OUTPUT_REPORT_URI

Output parameters (Get only): AUTOCORRELATION, CORRELATION, COVARIANCE, EIGENVALUES, EIGENVECTORS, MAX, MEAN, MIN, NPIXELS, STDDEV

Parameters marked as "Set" are those that you can set to specific values. You can also retrieve their current values any time. Parameters marked as "Get" are those whose values you can retrieve but not set.

Input Parameters

COMPUTE_COVARIANCE (optional)

Set this parameter to true to compute covariance matrix, eigenvectors, eigenvalues, and correlation on the raster. The options are true or false (default).

COMPUTE_HISTOGRAMS (optional)

Set this parameter to true to compute histograms. The result will be added to the report file specified by OUTPUT_REPORT_URI.

INPUT_RASTER (required)

Specify a raster from which to generate statistics.

OUTPUT_REPORT_URI (optional)

Specify a string with the fully qualified path and filename of a text file that will contain the statistics.

Output Parameters

AUTOCORRELATION

This is the autocorrelation matrix of the data.

CORRELATION

This is the correlation matrix of the data.

COVARIANCE

This is the covariance matrix of the data.

EIGENVALUES

This is an array of eigenvalues from the data.

EIGENVECTORS

This is an array of eigenvectors from the data.

MAX

This is the maximum data value of each band.

MEAN

This is the mean data value of each band.

MIN

This is the minimum data value of each band.

NPIXELS

This is the number of pixels in the raster.

STDDEV

This is the standard deviation data value of each band.

Methods

Execute

Parameter

ParameterNames

Properties

Version History

ENVI 5.2	Introduced
ENVI 5.5.3	Added COMPUTE_HISTOGRAMS and OUTPUT_REPORT_URI parameters
ENVI 6.2	Added AUTOCORRELATION parameter