getneighborhood_fast {DR.SC}

getneighborhood_fast

Description

an efficient function to find the neighborhood based on the matrix of position and a pre-defined cutoff

Usage

getneighborhood_fast(x, radius)

Arguments

x

is a n-by-2 matrix of position.

radius

is a threashold of Euclidean distance to decide whether a spot is an neighborhood of another spot. For example, if the Euclidean distance between spot A and B is less than cutoff, then A is taken as the neighbourhood of B.

Value

A sparse matrix containing the neighbourhood