com.google.zxing.common.detector.MathUtils Maven / Gradle / Ivy
/*
* Copyright 2012 ZXing authors
*
* 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.
*/
package com.google.zxing.common.detector;
/**
* General math-related and numeric utility functions.
*/
public final class MathUtils {
private MathUtils() {
}
/**
* Ends up being a bit faster than {@link Math#round(float)}. This merely rounds its
* argument to the nearest int, where x.5 rounds up to x+1. Semantics of this shortcut
* differ slightly from {@link Math#round(float)} in that half rounds down for negative
* values. -2.5 rounds to -3, not -2. For purposes here it makes no difference.
*
* @param d real value to round
* @return nearest {@code int}
*/
public static int round(float d) {
return (int) (d + (d < 0.0f ? -0.5f : 0.5f));
}
/**
* @param aX point A x coordinate
* @param aY point A y coordinate
* @param bX point B x coordinate
* @param bY point B y coordinate
* @return Euclidean distance between points A and B
*/
public static float distance(float aX, float aY, float bX, float bY) {
double xDiff = aX - bX;
double yDiff = aY - bY;
return (float) Math.sqrt(xDiff * xDiff + yDiff * yDiff);
}
/**
* @param aX point A x coordinate
* @param aY point A y coordinate
* @param bX point B x coordinate
* @param bY point B y coordinate
* @return Euclidean distance between points A and B
*/
public static float distance(int aX, int aY, int bX, int bY) {
double xDiff = aX - bX;
double yDiff = aY - bY;
return (float) Math.sqrt(xDiff * xDiff + yDiff * yDiff);
}
/**
* @param array values to sum
* @return sum of values in array
*/
public static int sum(int[] array) {
int count = 0;
for (int a : array) {
count += a;
}
return count;
}
}