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This is the api to interact with Concourse, a schemaless and distributed version control database with optimistic availability, serializable transactions and full-text search. Concourse provides a more intuitive approach to data management that is easy to deploy, access and scale with minimal tuning while also maintaining the referential integrity and ACID characteristics of traditional database systems.

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/*
 * The MIT License (MIT)
 * 
 * Copyright (c) 2013 Jeff Nelson, Cinchapi Software Collective
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package org.cinchapi.concourse.util;

import java.math.BigDecimal;

import static com.google.common.base.Preconditions.*;

/**
 * This class contains utility methods that provide interoperability for the
 * various {@link Number} types.
 * 
 * @author jnelson
 */
public abstract class Numbers {

	/**
	 * Return numerator/denominator as a percent.
	 * 
	 * @param numerator
	 * @param denominator
	 * @return the percent
	 */
	public static double percent(Number numerator, Number denominator) {
		return numerator.doubleValue() * 100.0 / denominator.doubleValue();
	}

	/**
	 * Compare {@code a} to {@code b}.
	 * 
	 * @param a
	 * @param b
	 * @return -1, 0, or 1 as {@code a} is numerically less than, equal to, or
	 *         greater than {@code b}.
	 */
	public static int compare(Number a, Number b) {
		//TODO review
		BigDecimal first = new BigDecimal(a.toString());
		BigDecimal second = new BigDecimal(b.toString());
		return first.compareTo(second);
	}

	/**
	 * Return {@code true} if {@code a} is mathematically greater than {@code b}
	 * 
	 * @param a
	 * @param b
	 * @return {@code true} if {@code a} > {@code b}
	 */
	public static boolean isGreaterThan(Number a, Number b) {
		return compare(a, b) > 0;
	}

	/**
	 * Return {@code true} if {@code a} is mathematically greater than or equal
	 * to {@code b}.
	 * 
	 * @param a
	 * @param b
	 * @return {@code true} if {@code a} >= {@code b}
	 */
	public static boolean isGreaterThanOrEqualTo(Number a, Number b) {
		return isGreaterThan(a, b) || isEqualTo(a, b);
	}

	/**
	 * Return {@code true} if {@code a} is mathematically less than or equal to
	 * {@code b}.
	 * 
	 * @param a
	 * @param b
	 * @return {@code true} if {@code a} <= {@code b}
	 */
	public static boolean isLessThanOrEqualTo(Number a, Number b) {
		return isLessThan(a, b) || isEqualTo(a, b);
	}

	/**
	 * Return {@code true} if {@code a} is mathematically less than {@code b}.
	 * 
	 * @param a
	 * @param b
	 * @return {@code true} if {@code a} < {@code b}
	 */
	public static boolean isLessThan(Number a, Number b) {
		return compare(a, b) < 0;
	}

	/**
	 * Return {@code true} if {@code a} is mathematically equal to {@code b}.
	 * 
	 * @param a
	 * @param b
	 * @return {@code true} if {@code a} == {@code b}
	 */
	public static boolean isEqualTo(Number a, Number b) {
		return compare(a, b) == 0;
	}

	/**
	 * Return {@code true} if {@code number} is evenly divisible by two.
	 * 
	 * @param number
	 * @return {@code true} if {@code number} is even.
	 */
	public static boolean isEven(Number number) {
		return number.intValue() % 2 == 0;
	}

	/**
	 * Return {@code true} if {@code number} is not evenly divisible by two.
	 * 
	 * @param number
	 * @return {@code true} if {@code number} is odd.
	 */
	public static boolean isOdd(Number number) {
		return !isEven(number);
	}

	/**
	 * Return the max from a list of {@code numbers}.
	 * 
	 * @param numbers
	 * @return the largest number
	 */
	public static Number max(Number... numbers) {
		Number max = numbers[0];
		for (Number number : numbers) {
			max = isGreaterThan(max, number) ? number : max;
		}
		return max;
	}

	/**
	 * Scale {@code number}, which is between {@code rawMin} and {@code rawMax}
	 * to a value between {@code scaledMin} and {@code scaleMax}.
	 * 
	 * @param number
	 * @param rawMin
	 * @param rawMax
	 * @param scaledMin
	 * @param scaledMax
	 * @return the scaled value
	 */
	public static Number scale(Number number, Number rawMin, Number rawMax,
			Number scaledMin, Number scaledMax) {
		checkArgument(isGreaterThanOrEqualTo(number, rawMin)
				&& isLessThanOrEqualTo(number, rawMax));

		double x = number.doubleValue();
		double min = rawMin.doubleValue();
		double max = rawMax.doubleValue();
		double a = scaledMin.doubleValue();
		double b = scaledMax.doubleValue();
		return (((b - a) * (x - min)) / (max - min)) + a;
	}
}