Java Number Power pow(double base, int exponent)

Description

pow

License

Apache License

Parameter

Parameter	Description
exponent	non-negative integer.

Declaration

static public double pow(double base, int exponent) 

Method Source Code

//package com.java2s;
/**//from  w  w  w .j  a v a2s .  co m
 * Copyright 2014, Emory University
 * 
 * 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 {
    /** @param exponent non-negative integer. */
    static public double pow(double base, int exponent) {
        if (exponent == 0)
            return 1;
        if (exponent == 1)
            return base;
        if (exponent == -1)
            return 1 / base;

        boolean negative;

        if (exponent < 0) {
            negative = true;
            exponent = -exponent;
        } else
            negative = false;

        double mod = (exponent % 2 == 0) ? 1 : base;
        double p = base;

        exponent /= 2;

        while (exponent > 0) {
            p = p * p;
            exponent /= 2;
        }

        mod *= p;
        return negative ? 1 / mod : mod;
    }
}

Related

1. pow(double a, double b)
2. pow(double a, int b)
3. pow(double base, double exp)
4. pow(double base, int exp)
5. pow(double base, int exp)
6. pow(double number)
7. Pow(double val, Object in)
8. Pow(double value)
9. pow(double value)