Create a Distance Matrix Between Two Sp Objects
This function creates a distance matrix between two sp objects (SpatialPointsDataFrame or SpatialPolygonsDataFrame).
sp object; rows of the distance matrix.
sp object; columns of the distance matrix.
logical; bypass the distance matrix size control (see Details).
The function returns a full matrix of distances in meters using the
Great Circle distance (WGS84 ellipsoid) method. This is a wrapper
If the matrix to compute is too large (more than 100,000,000 cells or more than 10,000,000 origins or destinations)
the function sends a confirmation message to warn users about the amount of RAM mobilized.
bypassctrl = TRUE to skip this control.
A distance matrix, row names are
knownpts row names, column names are
unknownpts row names.
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# Create a SpatialPointsDataFrame grid of spatMask extent and 200 meters # resolution data(spatData) mygrid <- CreateGrid(w = spatMask, resolution = 200) # Create a distance matrix between known spatPts and mygrid mymat <- CreateDistMatrix(knownpts = spatPts, unknownpts = mygrid, bypassctrl = FALSE) mymat[1:5,1:5] nrow(spatPts) nrow(mygrid) dim(mymat)