package mikera.vectorz.impl;

import java.util.Arrays;

import mikera.vectorz.AVector;
import mikera.vectorz.Op;
import mikera.vectorz.util.IntArrays;
import mikera.vectorz.util.VectorzException;

/**
 * Vector that addresses elements indexed into double[] array.
 * 
 * Useful for sub-selections views of array data
 * 
 * @author Mike
 */
public final class IndexedArrayVector extends BaseIndexedVector {
	private static final long serialVersionUID = 3220750778637547658L;

	private final double[] data;
	
	private IndexedArrayVector(double[] source, int[] indexes) {
		super(indexes);
		this.data=source;
	}
	
	/**
	 * Wraps the specified indexes into a double[] array as an IndexedArrayVector
	 * 
	 * The length of the vector will equal the number of indices provided.
	 * 
	 * @param data
	 * @param indexes
	 * @return
	 */
	public static IndexedArrayVector wrap(double[] data, int[] indexes) {
		return new IndexedArrayVector(data,indexes);
	}

	@Override
	public final double get(int i) {
		return data[indexes[i]];
	}
	
	@Override
	public final double unsafeGet(int i) {
		return data[indexes[i]];
	}
	
	@Override
	public IndexedArrayVector selectView(int... inds) {
		int[] ci=IntArrays.select(indexes,inds);
		return replaceIndex(ci);
	}

	@Override
	public final void set(int i, double value) {
		data[indexes[i]]=value;
	}
	
	@Override
	public final void unsafeSet(int i, double value) {
		data[indexes[i]]=value;
	}
	
	@Override
	public void addAt(int i, double value) {
		data[indexes[i]]+=value;
	}
	
	@Override
	public void applyOp(Op op) {
		for (int i=0; i