add part of opencv

Lib/opencv/sources/modules/ml/test/test_kmeans.cpp

@@ -0,0 +1,53 @@
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level directory
+// of this distribution and at http://opencv.org/license.html.
+
+#include "test_precomp.hpp"
+
+namespace opencv_test { namespace {
+
+TEST(ML_KMeans, accuracy)
+{
+    const int iters = 100;
+    int sizesArr[] = { 5000, 7000, 8000 };
+    int pointsCount = sizesArr[0]+ sizesArr[1] + sizesArr[2];
+
+    Mat data( pointsCount, 2, CV_32FC1 ), labels;
+    vector<int> sizes( sizesArr, sizesArr + sizeof(sizesArr) / sizeof(sizesArr[0]) );
+    Mat means;
+    vector<Mat> covs;
+    defaultDistribs( means, covs );
+    generateData( data, labels, sizes, means, covs, CV_32FC1, CV_32SC1 );
+    TermCriteria termCriteria( TermCriteria::COUNT, iters, 0.0);
+
+    {
+        SCOPED_TRACE("KMEANS_PP_CENTERS");
+        float err = 1000;
+        Mat bestLabels;
+        kmeans( data, 3, bestLabels, termCriteria, 0, KMEANS_PP_CENTERS, noArray() );
+        EXPECT_TRUE(calcErr( bestLabels, labels, sizes, err , false ));
+        EXPECT_LE(err, 0.01f);
+    }
+    {
+        SCOPED_TRACE("KMEANS_RANDOM_CENTERS");
+        float err = 1000;
+        Mat bestLabels;
+        kmeans( data, 3, bestLabels, termCriteria, 0, KMEANS_RANDOM_CENTERS, noArray() );
+        EXPECT_TRUE(calcErr( bestLabels, labels, sizes, err, false ));
+        EXPECT_LE(err, 0.01f);
+    }
+    {
+        SCOPED_TRACE("KMEANS_USE_INITIAL_LABELS");
+        float err = 1000;
+        Mat bestLabels;
+        labels.copyTo( bestLabels );
+        RNG &rng = cv::theRNG();
+        for( int i = 0; i < 0.5f * pointsCount; i++ )
+        bestLabels.at<int>( rng.next() % pointsCount, 0 ) = rng.next() % 3;
+        kmeans( data, 3, bestLabels, termCriteria, 0, KMEANS_USE_INITIAL_LABELS, noArray() );
+        EXPECT_TRUE(calcErr( bestLabels, labels, sizes, err, false ));
+        EXPECT_LE(err, 0.01f);
+    }
+}
+
+}} // namespace