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diff --git a/src/main/java/org/apache/commons/math3/analysis/interpolation/MicrosphereInterpolator.java b/src/main/java/org/apache/commons/math3/analysis/interpolation/MicrosphereInterpolator.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.math3.analysis.interpolation;
+
+import org.apache.commons.math3.analysis.MultivariateFunction;
+import org.apache.commons.math3.exception.NotPositiveException;
+import org.apache.commons.math3.exception.NotStrictlyPositiveException;
+import org.apache.commons.math3.exception.NoDataException;
+import org.apache.commons.math3.exception.DimensionMismatchException;
+import org.apache.commons.math3.exception.NullArgumentException;
+import org.apache.commons.math3.random.UnitSphereRandomVectorGenerator;
+
+/**
+ * Interpolator that implements the algorithm described in
+ * <em>William Dudziak</em>'s
+ * <a href="http://www.dudziak.com/microsphere.pdf">MS thesis</a>.
+ *
+ * @since 2.1
+ * @deprecated Code will be removed in 4.0.  Use {@link InterpolatingMicrosphere}
+ * and {@link MicrosphereProjectionInterpolator} instead.
+ */
+@Deprecated
+public class MicrosphereInterpolator
+    implements MultivariateInterpolator {
+    /**
+     * Default number of surface elements that composes the microsphere.
+     */
+    public static final int DEFAULT_MICROSPHERE_ELEMENTS = 2000;
+    /**
+     * Default exponent used the weights calculation.
+     */
+    public static final int DEFAULT_BRIGHTNESS_EXPONENT = 2;
+    /**
+     * Number of surface elements of the microsphere.
+     */
+    private final int microsphereElements;
+    /**
+     * Exponent used in the power law that computes the weights of the
+     * sample data.
+     */
+    private final int brightnessExponent;
+
+    /**
+     * Create a microsphere interpolator with default settings.
+     * Calling this constructor is equivalent to call {@link
+     * #MicrosphereInterpolator(int, int)
+     * MicrosphereInterpolator(MicrosphereInterpolator.DEFAULT_MICROSPHERE_ELEMENTS,
+     * MicrosphereInterpolator.DEFAULT_BRIGHTNESS_EXPONENT)}.
+     */
+    public MicrosphereInterpolator() {
+        this(DEFAULT_MICROSPHERE_ELEMENTS, DEFAULT_BRIGHTNESS_EXPONENT);
+    }
+
+    /** Create a microsphere interpolator.
+     * @param elements Number of surface elements of the microsphere.
+     * @param exponent Exponent used in the power law that computes the
+     * weights (distance dimming factor) of the sample data.
+     * @throws NotPositiveException if {@code exponent < 0}.
+     * @throws NotStrictlyPositiveException if {@code elements <= 0}.
+     */
+    public MicrosphereInterpolator(final int elements,
+                                   final int exponent)
+        throws NotPositiveException,
+               NotStrictlyPositiveException {
+        if (exponent < 0) {
+            throw new NotPositiveException(exponent);
+        }
+        if (elements <= 0) {
+            throw new NotStrictlyPositiveException(elements);
+        }
+
+        microsphereElements = elements;
+        brightnessExponent = exponent;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public MultivariateFunction interpolate(final double[][] xval,
+                                            final double[] yval)
+        throws DimensionMismatchException,
+               NoDataException,
+               NullArgumentException {
+        final UnitSphereRandomVectorGenerator rand
+            = new UnitSphereRandomVectorGenerator(xval[0].length);
+        return new MicrosphereInterpolatingFunction(xval, yval,
+                                                    brightnessExponent,
+                                                    microsphereElements,
+                                                    rand);
+    }
+}