/*
* 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.ignite.examples.ml.math.vector;
import java.util.Arrays;
import org.apache.ignite.ml.math.Matrix;
import org.apache.ignite.ml.math.Vector;
import org.apache.ignite.ml.math.VectorStorage;
import org.apache.ignite.ml.math.impls.matrix.DenseLocalOnHeapMatrix;
import org.apache.ignite.ml.math.impls.vector.AbstractVector;
/**
* This example shows how to use {@link Vector} based on custom {@link VectorStorage}.
*/
public final class VectorCustomStorageExample {
/**
* Executes example.
*
* @param args Command line arguments, none required.
*/
public static void main(String[] args) {
System.out.println();
System.out.println(">>> Vector custom storage API usage example started.");
System.out.println("\n>>> Creating perpendicular vectors.");
double[] data1 = new double[] {1, 0, 3, 0, 5, 0};
double[] data2 = new double[] {0, 2, 0, 4, 0, 6};
Vector v1 = new VectorCustomStorage(data1);
Vector v2 = new VectorCustomStorage(data2);
System.out.println(">>> First vector: " + Arrays.toString(data1));
System.out.println(">>> Second vector: " + Arrays.toString(data2));
double dotProduct = v1.dot(v2);
boolean dotProductIsAsExp = dotProduct == 0;
System.out.println("\n>>> Dot product of vectors: [" + dotProduct
+ "], it is 0 as expected: [" + dotProductIsAsExp + "].");
Vector hypotenuse = v1.plus(v2);
System.out.println("\n>>> Hypotenuse (sum of vectors): " + Arrays.toString(hypotenuse.getStorage().data()));
double lenSquared1 = v1.getLengthSquared();
double lenSquared2 = v2.getLengthSquared();
double lenSquaredHypotenuse = hypotenuse.getLengthSquared();
boolean lenSquaredHypotenuseIsAsExp = lenSquaredHypotenuse == lenSquared1 + lenSquared2;
System.out.println(">>> Squared length of first vector: [" + lenSquared1 + "].");
System.out.println(">>> Squared length of second vector: [" + lenSquared2 + "].");
System.out.println(">>> Squared length of hypotenuse: [" + lenSquaredHypotenuse
+ "], equals sum of squared lengths of two original vectors as expected: ["
+ lenSquaredHypotenuseIsAsExp + "].");
System.out.println("\n>>> Vector custom storage API usage example completed.");
}
/**
* Example of vector with custom storage, modeled after
* {@link org.apache.ignite.ml.math.impls.vector.DenseLocalOnHeapVector}.
*/
static class VectorCustomStorage extends AbstractVector {
/**
* @param arr Source array.
* @param cp {@code true} to clone array, reuse it otherwise.
*/
private VectorStorage mkStorage(double[] arr, boolean cp) {
assert arr != null;
return new ExampleVectorStorage(cp ? arr.clone() : arr);
}
/** */
public VectorCustomStorage() {
// No-op.
}
/**
* @param arr Source array.
* @param shallowCp {@code true} to use shallow copy.
*/
VectorCustomStorage(double[] arr, boolean shallowCp) {
setStorage(mkStorage(arr, shallowCp));
}
/**
* @param arr Source array.
*/
VectorCustomStorage(double[] arr) {
this(arr, false);
}
/** {@inheritDoc} */
@Override public Matrix likeMatrix(int rows, int cols) {
return new DenseLocalOnHeapMatrix(rows, cols);
}
/** {@inheritDoc */
@Override public Vector like(int crd) {
return new org.apache.ignite.ml.math.impls.vector.DenseLocalOnHeapVector(crd);
}
}
}