Java Array Normalize normalizeToOne(double[] doubles)

Description

normalize To One

License

Apache License

Declaration

public static double[] normalizeToOne(double[] doubles) 

Method Source Code

//package com.java2s;
/*-/*from www. j  a v  a  2 s  .  com*/
 *
 *  * Copyright 2015 Skymind,Inc.
 *  *
 *  *    Licensed 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.
 *
 */

public class Main {
    public static double[] normalizeToOne(double[] doubles) {
        normalize(doubles, sum(doubles));
        return doubles;
    }

    /**
     * Normalize a value
     * (val - min) / (max - min)
     * @param val value to normalize
     * @param max max value
     * @param min min value
     * @return the normalized value
     */
    public static double normalize(double val, double min, double max) {
        if (max < min)
            throw new IllegalArgumentException("Max must be greater than min");

        return (val - min) / (max - min);
    }

    /**
     * Normalizes the doubles in the array using the given value.
     *
     * @param doubles the array of double
     * @param sum the value by which the doubles are to be normalized
     * @exception IllegalArgumentException if sum is zero or NaN
     */
    public static void normalize(double[] doubles, double sum) {

        if (Double.isNaN(sum)) {
            throw new IllegalArgumentException("Can't normalize array. Sum is NaN.");
        }
        if (sum == 0) {
            // Maybe this should just be a return.
            throw new IllegalArgumentException("Can't normalize array. Sum is zero.");
        }
        for (int i = 0; i < doubles.length; i++) {
            doubles[i] /= sum;
        }
    }

    /**
     * This returns the sum of the given array.
     * @param nums the array of numbers to sum
     * @return the sum of the given array
     */
    public static double sum(double[] nums) {

        double ret = 0;
        for (double d : nums)
            ret += d;

        return ret;
    }
}

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5. normalizeToLogProbs(double[] x)
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7. normalizeTrimmedText(char[] ch)
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9. normalizeVector(double[] input)