VectorDimensionalityReduction - Vector Dimensionality Reduction¶

Performs dimensionality reduction of the input vector data according to a model file.

Detailed description¶

This application performs a vector data dimensionality reduction based on a model file produced by the TrainDimensionalityReduction application.

Parameters¶

This section describes in details the parameters available for this application. Table [1] presents a summary of these parameters and the parameters keys to be used in command-line and programming languages. Application key is VectorDimensionalityReduction .

[1]	Table: Parameters table for Vector Dimensionality Reduction.

Parameter Key	Parameter Name	Parameter Type
in	Name of the input vector data	Input vector data
instat	Statistics file	Input File name
model	Model file	Input File name
out	Output vector data file containing the reduced vector	Output File name
feat	Input features to use for reduction.	List
featout	Output feature	Choices
featout prefix	Prefix	Choice
featout list	List	Choice
featout.prefix.name	Feature name prefix	String
featout.list.names	Feature name list	String list
pcadim	Principal component dimension	Int
mode	Writing mode	Choices
mode overwrite	Overwrite	Choice
mode update	Update	Choice
inxml	Load otb application from xml file	XML input parameters file
outxml	Save otb application to xml file	XML output parameters file

Name of the input vector data: The input vector data to reduce.

Statistics file: A XML file containing mean and standard deviation to center and reduce samples before dimensionality reduction (produced by ComputeImagesStatistics application).

Model file: A model file (produced by the TrainDimensionalityReduction application,.

Output vector data file containing the reduced vector: Output vector data file storing sample values (OGR format). If not given, the input vector data file is used. In overwrite mode, the original features will be lost.

Input features to use for reduction.: List of field names in the input vector data used as features for reduction.

Output feature: Naming of output features. Available choices are:

Prefix: Use a name prefix.

Feature name prefix: Name prefix for output features. This prefix is followed by the numeric index of each output feature.

List: Use a list with all names.

Feature name list: List of field names for the output features which result from the reduction.

Principal component dimension: This optional parameter can be set to reduce the number of eignevectors used in the PCA model file. This parameter can’t be used for other models.

Writing mode: This parameter determines if the output file is overwritten or updated [overwrite/update]. If an output file name is given, the original file is copied before creating the new features. Available choices are:

Overwrite: Overwrite mode.
Update: Update mode.

Load otb application from xml file: Load otb application from xml file.

Save otb application to xml file: Save otb application to xml file.

Example¶

To run this example in command-line, use the following:

otbcli_VectorDimensionalityReduction -in vectorData.shp -instat meanVar.xml -model model.txt -out vectorDataOut.shp -feat perimeter area width

To run this example from Python, use the following code snippet:

#!/usr/bin/python

# Import the otb applications package
import otbApplication

# The following line creates an instance of the VectorDimensionalityReduction application
VectorDimensionalityReduction = otbApplication.Registry.CreateApplication("VectorDimensionalityReduction")

# The following lines set all the application parameters:
VectorDimensionalityReduction.SetParameterString("in", "vectorData.shp")

VectorDimensionalityReduction.SetParameterString("instat", "meanVar.xml")

VectorDimensionalityReduction.SetParameterString("model", "model.txt")

VectorDimensionalityReduction.SetParameterString("out", "vectorDataOut.shp")

# The following line execute the application
VectorDimensionalityReduction.ExecuteAndWriteOutput()

Limitations¶

None

Authors¶

This application has been written by OTB-Team.