// Copyright (c) Corporation for National Research Initiatives
package org.python.core.util;
/**
* A static utility class with two additional math functions.
*/
public class ExtraMath {
public static double EPSILON = Math.pow(2.0, -52.0);
public static double CLOSE = EPSILON * 2.0;
/**
* Are v and w "close" to each other? Uses a scaled tolerance.
*/
public static boolean close(double v, double w, double tol) {
if (v == w) {
return true;
}
double scaled = tol * (Math.abs(v) + Math.abs(w)) / 2.0;
return Math.abs(w - v) < scaled;
}
public static boolean close(double v, double w) {
return close(v, w, CLOSE);
}
/**
* Returns floor(v) except when v is very close to the next number, when it
* returns ceil(v);
*/
public static double closeFloor(double v) {
double floor = Math.floor(v);
return close(v, floor + 1.0) ? floor + 1.0 : floor;
}
}
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