(systemds) branch main updated: [MINOR] Fix and simplification kmeans-predict builtin function

[mboehm7]

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The following commit(s) were added to refs/heads/main by this push:
     new f1afbf46db [MINOR] Fix and simplification kmeans-predict builtin 
function
f1afbf46db is described below

commit f1afbf46db890c1475f9032981946c7351a4744e
Author: Matthias Boehm <mboe...@gmail.com>
AuthorDate: Fri Mar 15 13:37:06 2024 +0100

    [MINOR] Fix and simplification kmeans-predict builtin function
    
    This patch fixes the very convoluted computation of cluster
    assignments. For equal splits among clusters, we now use the last
    whereas before the first was used.
---
 scripts/builtin/kmeansPredict.dml | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/scripts/builtin/kmeansPredict.dml 
b/scripts/builtin/kmeansPredict.dml
index 29dc395b80..b619311896 100644
--- a/scripts/builtin/kmeansPredict.dml
+++ b/scripts/builtin/kmeansPredict.dml
@@ -35,11 +35,8 @@
 m_kmeansPredict = function(Matrix[Double] X, Matrix[Double] C)
   return (Matrix[Double] Y)
 {
- 
-    D =  -2 * (X %*% t(C)) + t(rowSums (C ^ 2));
-    P = (D <= rowMins (D));
-    aggr_P = t(cumsum (t(P)));
-    Y = rowSums (aggr_P == 0) + 1
-
+  D =  -2 * (X %*% t(C)) + t(rowSums(C^2));
+  P = (D <= rowMins (D));
+  Y = rowIndexMax(P);
 }