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GWmodel (version 2.4-1)

st.dist: 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)

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.

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

Author

Binbin Lu binbinlu@whu.edu.cn