From 8a3f8054fcfb5cef649b3ca4fb2dc7db3d565c28 Mon Sep 17 00:00:00 2001
From: Simon Garnier <garnier@njit.edu>
Date: Sat, 13 Jul 2024 17:48:14 +0200
Subject: [PATCH] Sampling doesn't have to be random

---
 R/gravitree.R | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/R/gravitree.R b/R/gravitree.R
index 33ea482..b6d72a6 100644
--- a/R/gravitree.R
+++ b/R/gravitree.R
@@ -1,5 +1,5 @@
 #' @export
-gravitree <- function(x, m, k = NULL, sample = 1, na_rm = FALSE) {
+gravitree <- function(x, m, k = NULL, sample = 1, random = TRUE, na_rm = FALSE) {
   if (!is.matrix(x)) {
     x <- as.matrix(x)
   }
@@ -25,7 +25,12 @@ gravitree <- function(x, m, k = NULL, sample = 1, na_rm = FALSE) {
   }
 
   if (sample < 1) {
-    ix <- sample(1:nr, nr * sample, prob = m)
+    if (random) {
+      ix <- sample(1:nr, nr * sample, prob = m)
+    } else {
+      ix <- order(m, decreasing = TRUE)[1:(nr * sample)]
+    }
+
     notix <- which(!(1:nr %in% ix))
     xx <- x[ix, , drop = FALSE]
     mm <- m[ix, , drop = FALSE]