Add PointPattern

Author: juliohm

Project.toml

@@ -6,10 +6,12 @@ version = "0.1.0"
 [deps]
 Distributions = "31c24e10-a181-5473-b8eb-7969acd0382f"
 GeoStatsBase = "323cb8eb-fbf6-51c0-afd0-f8fba70507b2"
+StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 
 [compat]
 Distributions = "0.21"
 GeoStatsBase = "0.7"
+StaticArrays = "0.12"
 julia = "1"
 
 [extras]

src/PointPatterns.jl

@@ -6,12 +6,22 @@ module PointPatterns
 
 using GeoStatsBase
 
-using Distributions
+using Distributions: Uniform, Poisson, product_distribution
+using StaticArrays: SVector, MVector
 
-# point processes
+import GeoStatsBase: npoints, coordinates, coordinates!
+
+include("pattern.jl")
 include("processes.jl")
 
 export
+  # point pattern
+  PointPattern,
+  npoints,
+  coordinates,
+  coordinates!,
+
+  # point processes
   PointProcess,
   BinomialProcess,
   PoissonProcess

src/pattern.jl

@@ -0,0 +1,89 @@
+# ------------------------------------------------------------------
+# Licensed under the ISC License. See LICENSE in the project root.
+# ------------------------------------------------------------------
+
+"""
+    PointPattern(coords)
+
+A set of points with coordinate matrix `coords`. The number of rows
+of the matrix is the dimensionality of the pattern whereas the number
+of columns is the number of points in the pattern. Alternatively, `coords`
+can be a vector of tuples (i.e. points).
+"""
+struct PointPattern{T,N}
+  coords::Matrix{T}
+end
+
+PointPattern(coords::AbstractMatrix{T}) where {T} =
+  PointPattern{T,size(coords,1)}(coords)
+
+PointPattern(coords::AbstractVector{NTuple{N,T}}) where {N,T} =
+  PointPattern([c[i] for i in 1:N, c in coords])
+
+npoints(pp::PointPattern) = size(pp.coords, 2)
+
+"""
+    coordinates(pp, ind)
+
+Return the coordinates of the `ind`-th point in the point pattern `pp`.
+"""
+function coordinates(pp::PointPattern{T,N}, ind::Int) where {N,T}
+  x = MVector{N,T}(undef)
+  coordinates!(x, pp, ind)
+  x
+end
+
+"""
+    coordinates(pp, inds)
+
+Return the coordinates of the points `inds` in the point pattern `pp`.
+"""
+function coordinates(pp::PointPattern{T,N}, inds::AbstractVector{Int}) where {N,T}
+  X = Matrix{T}(undef, N, length(inds))
+  coordinates!(X, pp, inds)
+  X
+end
+
+"""
+    coordinates(pp)
+
+Return the coordinates of all points in point pattern `pp`.
+"""
+coordinates(pp::PointPattern) = coordinates(pp, 1:npoints(pp))
+
+"""
+    coordinates!(buff, pp, inds)
+
+Non-allocating version of [`coordinates`](@ref)
+"""
+function coordinates!(buff::AbstractMatrix, pp::PointPattern,
+                      inds::AbstractVector{Int})
+  for j in 1:length(inds)
+    coordinates!(view(buff,:,j), pp, inds[j])
+  end
+end
+
+"""
+    coordinates!(buff, pp, ind)
+
+Non-allocating version of [`coordinates`](@ref).
+"""
+function coordinates!(buff::AbstractVector{T}, pp::PointPattern{T,N},
+                      ind::Int) where {N,T}
+  for i in 1:N
+    @inbounds buff[i] = pp.coords[i,ind]
+  end
+end
+
+# ------------
+# IO methods
+# ------------
+function Base.show(io::IO, pp::PointPattern{T,N}) where {N,T}
+  npts = size(pp.coords, 2)
+  print(io, "$npts PointPattern{$T,$N}")
+end
+
+function Base.show(io::IO, ::MIME"text/plain", pp::PointPattern{T,N}) where {N,T}
+  println(io, pp)
+  Base.print_array(io, pp.coords)
+end

src/processes/binomial.jl

@@ -20,5 +20,5 @@ function rand_single(p::BinomialProcess, r::RectangleRegion{T,N}) where {N,T}
   U = product_distribution([Uniform(lo[i], up[i]) for i in 1:N])
 
   # return point pattern
-  PointSet(rand(U, p.n))
+  PointPattern(rand(U, p.n))
 end

src/processes/poisson.jl

@@ -25,5 +25,5 @@ function rand_single(p::PoissonProcess, r::RectangleRegion{T,N}) where {N,T}
   U = product_distribution([Uniform(lo[i], up[i]) for i in 1:N])
 
   # return point pattern
-  PointSet(rand(U, n))
+  PointPattern(rand(U, n))
 end