home | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (TricubicInterpolator.java)

This example Java source code file (TricubicInterpolator.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

dimensionmismatchexception, nodataexception, nonmonotonicsequenceexception, numberistoosmallexception, override, tricubicinterpolatingfunction, tricubicinterpolator, trivariategridinterpolator

The TricubicInterpolator.java Java example source code

/*
 * 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.exception.DimensionMismatchException;
import org.apache.commons.math3.exception.NoDataException;
import org.apache.commons.math3.exception.NonMonotonicSequenceException;
import org.apache.commons.math3.exception.NumberIsTooSmallException;
import org.apache.commons.math3.util.MathArrays;

/**
 * Generates a tricubic interpolating function.
 *
 * @since 3.4
 */
public class TricubicInterpolator
    implements TrivariateGridInterpolator {
    /**
     * {@inheritDoc}
     */
    public TricubicInterpolatingFunction interpolate(final double[] xval,
                                                     final double[] yval,
                                                     final double[] zval,
                                                     final double[][][] fval)
        throws NoDataException, NumberIsTooSmallException,
               DimensionMismatchException, NonMonotonicSequenceException {
        if (xval.length == 0 || yval.length == 0 || zval.length == 0 || fval.length == 0) {
            throw new NoDataException();
        }
        if (xval.length != fval.length) {
            throw new DimensionMismatchException(xval.length, fval.length);
        }

        MathArrays.checkOrder(xval);
        MathArrays.checkOrder(yval);
        MathArrays.checkOrder(zval);

        final int xLen = xval.length;
        final int yLen = yval.length;
        final int zLen = zval.length;

        // Approximation to the partial derivatives using finite differences.
        final double[][][] dFdX = new double[xLen][yLen][zLen];
        final double[][][] dFdY = new double[xLen][yLen][zLen];
        final double[][][] dFdZ = new double[xLen][yLen][zLen];
        final double[][][] d2FdXdY = new double[xLen][yLen][zLen];
        final double[][][] d2FdXdZ = new double[xLen][yLen][zLen];
        final double[][][] d2FdYdZ = new double[xLen][yLen][zLen];
        final double[][][] d3FdXdYdZ = new double[xLen][yLen][zLen];

        for (int i = 1; i < xLen - 1; i++) {
            if (yval.length != fval[i].length) {
                throw new DimensionMismatchException(yval.length, fval[i].length);
            }

            final int nI = i + 1;
            final int pI = i - 1;

            final double nX = xval[nI];
            final double pX = xval[pI];

            final double deltaX = nX - pX;

            for (int j = 1; j < yLen - 1; j++) {
                if (zval.length != fval[i][j].length) {
                    throw new DimensionMismatchException(zval.length, fval[i][j].length);
                }

                final int nJ = j + 1;
                final int pJ = j - 1;

                final double nY = yval[nJ];
                final double pY = yval[pJ];

                final double deltaY = nY - pY;
                final double deltaXY = deltaX * deltaY;

                for (int k = 1; k < zLen - 1; k++) {
                    final int nK = k + 1;
                    final int pK = k - 1;

                    final double nZ = zval[nK];
                    final double pZ = zval[pK];

                    final double deltaZ = nZ - pZ;

                    dFdX[i][j][k] = (fval[nI][j][k] - fval[pI][j][k]) / deltaX;
                    dFdY[i][j][k] = (fval[i][nJ][k] - fval[i][pJ][k]) / deltaY;
                    dFdZ[i][j][k] = (fval[i][j][nK] - fval[i][j][pK]) / deltaZ;

                    final double deltaXZ = deltaX * deltaZ;
                    final double deltaYZ = deltaY * deltaZ;

                    d2FdXdY[i][j][k] = (fval[nI][nJ][k] - fval[nI][pJ][k] - fval[pI][nJ][k] + fval[pI][pJ][k]) / deltaXY;
                    d2FdXdZ[i][j][k] = (fval[nI][j][nK] - fval[nI][j][pK] - fval[pI][j][nK] + fval[pI][j][pK]) / deltaXZ;
                    d2FdYdZ[i][j][k] = (fval[i][nJ][nK] - fval[i][nJ][pK] - fval[i][pJ][nK] + fval[i][pJ][pK]) / deltaYZ;

                    final double deltaXYZ = deltaXY * deltaZ;

                    d3FdXdYdZ[i][j][k] = (fval[nI][nJ][nK] - fval[nI][pJ][nK] -
                                          fval[pI][nJ][nK] + fval[pI][pJ][nK] -
                                          fval[nI][nJ][pK] + fval[nI][pJ][pK] +
                                          fval[pI][nJ][pK] - fval[pI][pJ][pK]) / deltaXYZ;
                }
            }
        }

        // Create the interpolating function.
        return new TricubicInterpolatingFunction(xval, yval, zval, fval,
                                                 dFdX, dFdY, dFdZ,
                                                 d2FdXdY, d2FdXdZ, d2FdYdZ,
                                                 d3FdXdYdZ) {
            /** {@inheritDoc} */
            @Override
            public boolean isValidPoint(double x, double y, double z) {
                if (x < xval[1] ||
                    x > xval[xval.length - 2] ||
                    y < yval[1] ||
                    y > yval[yval.length - 2] ||
                    z < zval[1] ||
                    z > zval[zval.length - 2]) {
                    return false;
                } else {
                    return true;
                }
            }
        };
    }
}

Other Java examples (source code examples)

Here is a short list of links related to this Java TricubicInterpolator.java source code file:



my book on functional programming

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.