From: Ben Pfaff <blp@cs.stanford.edu>
Date: Tue, 28 Jan 2025 22:22:51 +0000 (-0800)
Subject: QUICK CLUSTER: Use fixed format for cluster centers.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2284baf7ab2097e7655a376ef7a6f9146a18f952;p=pspp

QUICK CLUSTER: Use fixed format for cluster centers.

This command used the variables' own formats for their centers.  This was
a bad idea for at least two reasons.  First, the variables might have a
format that does not show any decimal places, but clusters wouldn't
ordinarily have integer centers, so this is confusing.  Second, if a
cluster center happens to have a value label, it could be shown instead,
which is even more confusing.  This fixes the problem by using a fixed
format instead.

Thanks to Andreas Hammer for reporting the problem.
---

diff --git a/src/language/commands/quick-cluster.c b/src/language/commands/quick-cluster.c
index 128130afe3..cb58170069 100644
--- a/src/language/commands/quick-cluster.c
+++ b/src/language/commands/quick-cluster.c
@@ -549,9 +549,7 @@ quick_cluster_show_centers (struct Kmeans *kmeans, bool initial, const struct qc
     for (size_t j = 0; j < qc->n_vars; j++)
       {
         double x = gsl_matrix_get (matrix, kmeans->group_order->data[i], j);
-        union value v = { .f = x };
-        pivot_table_put2 (table, i, j,
-                          pivot_value_new_var_value (qc->vars[j], &v));
+        pivot_table_put2 (table, i, j, pivot_value_new_number (x));
       }
 
   pivot_table_submit (table);
diff --git a/tests/language/commands/quick-cluster.at b/tests/language/commands/quick-cluster.at
index 12f4b2ac43..f467d1d6b2 100644
--- a/tests/language/commands/quick-cluster.at
+++ b/tests/language/commands/quick-cluster.at
@@ -350,14 +350,14 @@ AT_CHECK([pspp -O format=csv quick-cluster.sps], [0], [dnl
 Table: Initial Cluster Centers
 ,Cluster,,
 ,1,2,3
-x,-11,-12,11
-y,-12,11,11
+x,-10.80,-11.65,11.10
+y,-11.76,10.81,10.91
 
 Table: Final Cluster Centers
 ,Cluster,,
 ,1,2,3
-x,-10,-10,10
-y,-10,10,10
+x,-10.22,-10.14,10.28
+y,-10.01,10.22,9.89
 
 Table: Number of Cases in each Cluster
 ,,Count