Java Array Sum Square sumSquares(final float[] a)

Description

sum Squares

License

Apache License

Declaration

public static float sumSquares(final float[] a) 

Method Source Code

//package com.java2s;
//License from project: Apache License 

public class Main {
    public static float sumSquares(final float[] a) {
        return sumSquares(a, 0, a.length);
    }//w  w  w . j av a  2 s  . c o  m

    public static float sumSquares(final float[] a, int from, int to) {
        float result = 0;
        final int cols = to - from;
        final int extra = cols - cols % 8;
        final int multiple = (cols / 8) * 8 - 1;
        float psum1 = 0, psum2 = 0, psum3 = 0, psum4 = 0;
        float psum5 = 0, psum6 = 0, psum7 = 0, psum8 = 0;
        for (int c = from; c < from + multiple; c += 8) {
            psum1 += a[c + 0] * a[c + 0];
            psum2 += a[c + 1] * a[c + 1];
            psum3 += a[c + 2] * a[c + 2];
            psum4 += a[c + 3] * a[c + 3];
            psum5 += a[c + 4] * a[c + 4];
            psum6 += a[c + 5] * a[c + 5];
            psum7 += a[c + 6] * a[c + 6];
            psum8 += a[c + 7] * a[c + 7];
        }
        result += psum1 + psum2 + psum3 + psum4;
        result += psum5 + psum6 + psum7 + psum8;
        for (int c = from + extra; c < to; ++c) {
            result += a[c] * a[c];
        }
        return result;
    }
}

Related

1. sumSquaredError(double[] a, double[] b)
2. sumSquareDev(double[] values, double target)
3. sumSquareDoubleArray(double[] v)
4. sumSquares(double[] aArray)
5. sumSquares(double[] data)
6. sumSquares(float[] in)
7. sumValuesSquared(double[] vector)