getVectorSetListFeatures {openSkies}

Get positional features of a list of openSkiesStateVectorSet objects

Description

Retrieves positional features of a list of openSkiesStateVectorSet objects. Features will be uniformly interpolated from the observed values for all the openSkiesStateVectorSet objects.

Usage

getVectorSetListFeatures(stateVectorSetList, resamplingSize=15, method="fmm", 
                         scale=TRUE, fields=NULL)

Arguments

stateVectorSetList

list of objects of class openSkiesStateVectorSet for which positional features should be extracted.

resamplingSize

number of uniformly separated interpolation points at which the values of the position features should be calculated.

method

method to be used for interpolation. "linear" will result in linear interpolation, while "fmm", "periodic", or "natural" will result in different types of spline interpolation.

scale

logical indicating if the matrix of features should be scaled by applying the scale function. This can be desirable if the features are going to be used for clustering.

fields

character vector indicating the names of the fields of the openSkiesStateVector objects that should be included in the extracted positional features. In the default behavior, fields=NULL and only latitude and longitude values will be used.

Value

A matrix with positional features of the provided list of openSkiesStateVectorSet objects. Each row of the matrix represents a vector of features for each of the openSkiesStateVectorSet objects. Each vector alternates values of longitude and latitude at each interpolated point, unless a character vector with valid names of fields of openSkiesStateVector objects is provided through fields, in which case values of the specified fields are alternated, in the specified order.

Examples

# Extract positional features for a time series of state vectors for the 
# aircraft with ICAO 24-bit address 403003 for the 8th of October, 2020 between 
# 16:50 and 16:53 (London time), with a time resolution of 1 minute.

if(interactive()){
vectors1=getAircraftStateVectorsSeries(aircraft="345107", 
startTime="2020-11-04 11:55:00", endTime="2020-11-04 13:10:00", 
timeZone="Europe/London", timeResolution=300)

vectors2=getAircraftStateVectorsSeries(aircraft = "4ca7b3", 
startTime="2020-11-04 10:30:00", endTime="2020-11-04 12:00:00",
timeZone="Europe/London", timeResolution=300)

vectors_list=list(vectors1, vectors2)

features_matrix=getVectorSetListFeatures(vectors_list, scale=FALSE, 
                                         fields=c("longitude", "latitude", "true_track"))
}