st.dist: Spatio-temporal distance matrix calculation
In GWmodel: Geographically-Weighted Models

st.dist

R Documentation

Spatio-temporal distance matrix calculation

Description

Calculate a distance vector(matrix) between any GW model calibration point(s) and the data points.

Usage

st.dist(dp.locat, rp.locat, obs.tv, reg.tv,focus=0, p=2, 
        theta=0, longlat=F,lamda=0.05,t.units = "auto",
        ksi=0, s.dMat,t.dMat)

Arguments

`dp.locat`	a numeric matrix of two columns giving the coordinates of the data points
`rp.locat`	a numeric matrix of two columns giving the coordinates of the GW model calibration points
`obs.tv`	a vector of time tags for each observation, which could be numeric or of POSIXlt class
`reg.tv`	a vector of time tags for each regression location, which could be numeric or of POSIXlt class
`focus`	an integer, indexing to the current GW model point, if focus=0, all the distances between all the GW model calibration points and data points will be calculated and a distance matrix will be returned; if 0<focus<length(rp.locat), then the distances between the 'focus'th GW model points and data points will be calculated and a distance vector will be returned
`p`	the power of the Minkowski distance, default is 2, i.e. the Euclidean distance
`theta`	an angle in radians to rotate the coordinate system, default is 0
`longlat`	if TRUE, great circle distances will be calculated
`lamda`	an parameter between 0 and 1 for calculating spatio-temporal distance
`t.units`	character string to define time unit
`ksi`	an parameter between 0 and PI for calculating spatio-temporal distance, see details in Wu et al. (2014)
`s.dMat`	a predifined spatial distance matrix for calculating spatio-temporal distances
`t.dMat`	a predifined temporal distance matrix for calculating spatio-temporal distances

Value

Returns a numeric spatio-temporal distance matrix or vector; or a matrix with its rows corresponding to the observations and its columns corresponds to the calibration points.