Merged IBPSA with correction for kMeans and for wind cut-out speed

mwetter · mwetter · commit 9d9837655b24 · 2025-04-09T14:14:01.000-07:00
diff --git a/Buildings/Electrical/BaseClasses/WindTurbine/PartialWindTurbine.mo b/Buildings/Electrical/BaseClasses/WindTurbine/PartialWindTurbine.mo
@@ -15,8 +15,8 @@ protected
   Modelica.Blocks.Tables.CombiTable1Ds per(
     final tableOnFile=tableOnFile,
     final table=cat(1, cat(1, [0, 0], table),
-                    [vOut+10*Modelica.Constants.eps, 0;
-                     vOut+20*Modelica.Constants.eps, 0]),
+                    [vOut+1E-9, 0;
+                     vOut+2E-9, 0]),
     final tableName=tableName,
     final fileName=fileName,
     final columns=2:2,
@@ -170,10 +170,15 @@ Below and above these wind speeds, the generated power is zero.
 </html>", revisions="<html>
 <ul>
 <li>
+April 9, 2025, by Michael Wetter:<br/>
+Increased small number to extend table beyond cut-out wind speed.<br/>
+<a href=\"https://github.com/lbl-srg/modelica-Buildings/issues/1996\">IBPSA, issue 1996</a>.
+</li>
+<li>
 March 1, 2016, by Michael Wetter:<br/>
 Removed test for equality of <code>Real</code> variables.
 This is for
-<a href=\"https://github.com/lbl-srg/modelica-Buildings/issues/493\">issue 493</a>.
+<a href=\"https://github.com/lbl-srg/modelica-buildings/issues/493\">issue 493</a>.
 </li>
 <li>
 January 10, 2013, by Michael Wetter:<br/>
diff --git a/Buildings/Fluid/Geothermal/Borefields/BaseClasses/HeatTransfer/ThermalResponseFactors/Validation/ClusterBoreholes_100boreholes.mo b/Buildings/Fluid/Geothermal/Borefields/BaseClasses/HeatTransfer/ThermalResponseFactors/Validation/ClusterBoreholes_100boreholes.mo
@@ -15,10 +15,11 @@ model ClusterBoreholes_100boreholes
   parameter Integer cluSiz[k](each fixed=false) "Size of the clusters";
 
   parameter Integer labelsExp[nBor]=
-    {3, 3, 3, 4, 4, 4, 4, 3, 3, 3, 3, 4, 4, 2, 2, 2, 2, 4, 4, 3, 3, 4, 2, 2, 1,
-     1, 2, 2, 4, 3, 4, 2, 2, 1, 1, 1, 1, 2, 2, 4, 4, 2, 1, 1, 1, 1, 1, 1, 2, 4,
-     4, 2, 1, 1, 1, 1, 1, 1, 2, 4, 4, 2, 2, 1, 1, 1, 1, 2, 2, 4, 3, 4, 2, 2, 1,
-     1, 2, 2, 4, 3, 3, 4, 4, 2, 2, 2, 2, 4, 4, 3, 3, 3, 3, 4, 4, 4, 4, 3, 3, 3}
+    {1, 1, 2, 2, 2, 2, 2, 2, 1, 1, 1, 2, 4, 4, 4, 4, 4, 4, 2, 1, 2, 4, 4, 3,
+     3, 3, 3, 4, 4, 2, 2, 4, 3, 3, 3, 3, 3, 3, 4, 2, 2, 4, 3, 3, 3, 3, 3, 3,
+     4, 2, 2, 4, 3, 3, 3, 3, 3, 3, 4, 2, 2, 4, 3, 3, 3, 3, 3, 3, 4, 2, 2, 4,
+     4, 3, 3, 3, 3, 4, 4, 2, 1, 2, 4, 4, 4, 4, 4, 4, 2, 1, 1, 1, 2, 2, 2, 2,
+     2, 2, 1, 1}
     "Expected cluster labels";
 
   // Comparison result
diff --git a/Buildings/UsersGuide/ReleaseNotes/Version_12_0_1.mo b/Buildings/UsersGuide/ReleaseNotes/Version_12_0_1.mo
@@ -40,12 +40,25 @@ have been <b style=\"color:blue\">improved</b> in a
 <b style=\"color:blue\">backward compatible</b> way:
 </p>
 <table class=\"releaseTable\" summary=\"summary\" border=\"1\" cellspacing=\"0\" cellpadding=\"2\" style=\"border-collapse:collapse;\">
-<tr><td colspan=\"2\"><b>xxx</b>
+<tr><td colspan=\"2\"><b>Buildings.Fluid.Geothermal</b><br/>
+                         Buildings.Utilities.Clustering
     </td>
 </tr>
-<tr><td valign=\"top\">xxx
+<tr><td colspan=\"2\"><b>Buildings.Electrical</b>
     </td>
-    <td valign=\"top\">xxx.
+</tr>
+<tr><td valign=\"top\">Buildings.Electrical.BaseClasses.WindTurbine.PartialWindTurbine
+    </td>
+    <td valign=\"top\">Changed model to avoid a rounding error that occurs due to the revised definition of <ocde>eps</code>
+                       in the development version of the Modelica Standard Library 4.1.0.<br/>
+                       This is for <a href=\"https://github.com/ibpsa/modelica-ibpsa/issues/1996\">IBPSA, #1996</a>.
+    </td>
+</tr>
+<tr><td valign=\"top\">Buildings.Utilities.Clustering.KMeans
+    </td>
+    <td valign=\"top\">Improved code to avoid an error during initialization of certain borefield geometries.<br/>
+                       This is for <a href=\"https://github.com/ibpsa/modelica-ibpsa/issues/1985\">IBPSA, #1985</a> and
+                       <a href=\"https://github.com/ibpsa/modelica-ibpsa/issues/1976\">IBPSA, #1976</a>.
     </td>
 </tr>
 <tr><td colspan=\"2\"><b>xxx</b>
@@ -113,4 +126,4 @@ xxx
 </li>
 </ul>
 </html>"));
-end Version_12_0_1;
+end Version_12_0_1;
diff --git a/Buildings/Utilities/Clustering/KMeans.mo b/Buildings/Utilities/Clustering/KMeans.mo
@@ -6,6 +6,7 @@ impure function KMeans "k-means clustering algorithm"
   input Integer n_samples "Number of samples";
   input Integer n_features "Number of features";
   input Real relTol=1e-5 "Relative tolerance on cluster positions";
+  input Real absTol=1e-8 "Absolute tolerance on cluster positions";
   input Integer max_iter=500 "Maximum number of k-means iterations";
   input Integer n_init=10 "Number of runs with randomized centroid seeds";
   input Integer n_cluster_size=0 "Length of the cluster_size output vector";
@@ -16,7 +17,8 @@ impure function KMeans "k-means clustering algorithm"
 protected
   Real old_centroids[n_clusters,n_features] "Previous iteration centroids";
   Real new_centroids[n_clusters,n_features] "Next iteration centroids";
-  Real delta_centroids "Maximum relative displacement of cluster centroids between two k-means iterations";
+  Real relDelta_centroids "Maximum relative displacement of cluster centroids between two k-means iterations";
+  Real absDelta_centroids "Maximum absolute displacement of cluster centroids between two k-means iterations";
   Integer new_labels[n_samples] "Next iteration cluster labels";
   Real new_inertia "Inertia of the samples during the current run";
   Real inertia "Minimum inertia of the samples since first run";
@@ -31,30 +33,30 @@ algorithm
  id := Modelica.Math.Random.Utilities.initializeImpureRandom(seed);
 
   // ---- Perform n_init successive runs of the k-means algorithm
- for run in 1:n_init loop
+  inertia := Modelica.Constants.inf;
+  for run in 1:n_init loop
     // ---- Select initial centroids at random
     // Select 3 non-repeated data points in the data set
     n := Modelica.Math.Random.Utilities.impureRandomInteger(id,1,n_samples);
     old_centroids[1,:] := data[n,:];
     for i in 2:n_clusters loop
-      n := Modelica.Math.Random.Utilities.impureRandomInteger(id,1,n_samples);
-      old_centroids[i,:] := data[n,:];
-      min_dis := Modelica.Math.Vectors.norm(old_centroids[i,:]-old_centroids[1,:], p=2)^2;
+      min_dis := 0;
       while min_dis < Modelica.Constants.eps loop
         n := Modelica.Math.Random.Utilities.impureRandomInteger(id,1,n_samples);
         old_centroids[i,:] := data[n,:];
         min_dis := Modelica.Math.Vectors.norm(old_centroids[i,:]-old_centroids[1,:], p=2)^2;
-        for j in 1:i-1 loop
-          dis := Modelica.Math.Vectors.norm(old_centroids[j,:]-old_centroids[i,:], p=2)^2;
+        for j in 2:i-1 loop
+          dis := Modelica.Math.Vectors.norm(old_centroids[i,:]-old_centroids[j,:], p=2)^2;
           min_dis := min(dis, min_dis);
         end for;
       end while;
     end for;
 
     // ---- k-means iterations
     k_iter := 0;
-    delta_centroids := 2*relTol;
-    while k_iter < max_iter and delta_centroids > relTol loop
+    relDelta_centroids := 2*relTol;
+    absDelta_centroids := 2*absTol;
+    while k_iter < max_iter and (relDelta_centroids > relTol or absDelta_centroids > absTol) loop
       k_iter := k_iter + 1;
 
       // Find centroid closest to each data point
@@ -71,7 +73,8 @@ algorithm
       end for;
 
       // Re-evaluate position of the centroids
-      delta_centroids := 0;
+      relDelta_centroids := 0;
+      absDelta_centroids := 0;
       for j in 1:n_clusters loop
         n := sum(if new_labels[i]==j then 1 else 0 for i in 1:n_samples);
         new_centroids[j,:] := zeros(n_features);
@@ -84,7 +87,8 @@ algorithm
         else
           new_centroids[j,:] := old_centroids[j,:];
         end if;
-        delta_centroids := max(delta_centroids, sum((new_centroids[j,:] - old_centroids[j,:])./old_centroids[j,:]));
+        relDelta_centroids := max(relDelta_centroids, sum(abs(new_centroids[j,:] - old_centroids[j,:]) ./ (abs(old_centroids[j,:]) .+ Modelica.Constants.eps)));
+        absDelta_centroids := max(absDelta_centroids, sum(abs(new_centroids[j,:] - old_centroids[j,:])));
       end for;
       old_centroids := new_centroids;
     end while;
@@ -93,7 +97,7 @@ algorithm
     new_inertia := 0;
     for i in 1:n_samples loop
       dis := Modelica.Math.Vectors.norm(data[i,:]-centroids[new_labels[i],:], p=2)^2;
-      new_inertia := inertia + dis;
+      new_inertia := new_inertia + dis;
     end for;
 
     // Keep run results if inertia is minimum
@@ -129,6 +133,15 @@ modifying the constant <code>seed</code>.
 </html>", revisions="<html>
 <ul>
 <li>
+March 18, 2025 by Massimo Cimmino<br/>
+Added absolute tolerance. The algorithm stops when any of the relative and
+absolute tolerances is satisfied. This fixes errors that occur when a centroid
+has a value close to zero on any of its axes. See
+<a href=\"https://github.com/ibpsa/modelica-ibpsa/issues/1985\">#1985</a>.
+Fixed the initial selection of centroids to avoid repeated centroids. See also
+<a href=\"https://github.com/ibpsa/modelica-ibpsa/issues/1976\">#1976</a>.
+</li>
+<li>
 February 1, 2023, by Michael Wetter:<br/>
 Added <code>impure</code> declaration which is needed for compliance with the Modelica Language Specification,
 and is required by Optimica.
diff --git a/Buildings/Utilities/Clustering/Validation/KMeans_1d.mo b/Buildings/Utilities/Clustering/Validation/KMeans_1d.mo
@@ -15,7 +15,7 @@ model KMeans_1d "Model that verifies the k-means clustering function for 1d data
     "Size of the clusters";
 
   parameter Integer labelsExp[nDat]=
-    {2,2,2,1,3}
+    {3,2,2,1,1}
     "Expected cluster labels";
 
   // Comparison result
diff --git a/Buildings/Utilities/Clustering/Validation/KMeans_2d.mo b/Buildings/Utilities/Clustering/Validation/KMeans_2d.mo
@@ -22,7 +22,7 @@ model KMeans_2d "Model that verifies the k-means clustering function for 2d data
     "Size of the clusters";
 
   parameter Integer labelsExp[nDat]=
-    {2,2,1,2,1,3}
+    {3,3,2,2,1,1}
     "Expected cluster labels";
 
   // Comparison result
