R/idist.R

In doserjef/spOccupancy: Single-Species, Multi-Species, and Integrated Spatial Occupancy Models

iDist <- function(coords.1, coords.2, ...){
  
    if(!is.matrix(coords.1))
      coords.1 <- as.matrix(coords.1)

    if(missing(coords.2))
      coords.2 <- coords.1

    if(!is.matrix(coords.2))
      coords.2 <- as.matrix(coords.2)

    if(ncol(coords.1) != ncol(coords.2))
      stop("error: ncol(coords.1) != ncol(coords.2)")

    p <- ncol(coords.1)
    n1 <- nrow(coords.1)
    n2 <- nrow(coords.2)
   
    
    D <- matrix(0, n1, n2)

    storage.mode(coords.1) <- "double"
    storage.mode(coords.2) <- "double"
    storage.mode(D) <- "double"
    storage.mode(n1) <- "integer"
    storage.mode(n2) <- "integer"
    storage.mode(p) <- "integer"
    
    .Call("idist", coords.1, n1, coords.2, n2, p, D)
    D
  }