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diff --git a/src/main/java/org/apache/commons/math3/analysis/interpolation/TrivariateGridInterpolator.java b/src/main/java/org/apache/commons/math3/analysis/interpolation/TrivariateGridInterpolator.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.TrivariateFunction;
+import org.apache.commons.math3.exception.DimensionMismatchException;
+import org.apache.commons.math3.exception.NoDataException;
+import org.apache.commons.math3.exception.NonMonotonicSequenceException;
+import org.apache.commons.math3.exception.NumberIsTooSmallException;
+
+/**
+ * Interface representing a trivariate real interpolating function where the
+ * sample points must be specified on a regular grid.
+ *
+ * @since 2.2
+ */
+public interface TrivariateGridInterpolator {
+    /**
+     * Compute an interpolating function for the dataset.
+     *
+     * @param xval All the x-coordinates of the interpolation points, sorted
+     * in increasing order.
+     * @param yval All the y-coordinates of the interpolation points, sorted
+     * in increasing order.
+     * @param zval All the z-coordinates of the interpolation points, sorted
+     * in increasing order.
+     * @param fval the values of the interpolation points on all the grid knots:
+     * {@code fval[i][j][k] = f(xval[i], yval[j], zval[k])}.
+     * @return a function that interpolates the data set.
+     * @throws NoDataException if any of the arrays has zero length.
+     * @throws DimensionMismatchException if the array lengths are inconsistent.
+     * @throws NonMonotonicSequenceException if arrays are not sorted
+     * @throws NumberIsTooSmallException if the number of points is too small for
+     * the order of the interpolation
+     */
+    TrivariateFunction interpolate(double[] xval, double[] yval, double[] zval,
+                                   double[][][] fval)
+        throws NoDataException, NumberIsTooSmallException,
+               DimensionMismatchException, NonMonotonicSequenceException;
+}