Here you can find the source of minute(double serial_number)
public static final double minute(double serial_number)
//package com.java2s; //License from project: Apache License public class Main { public static final double minute(double serial_number) { if (!isFinite(serial_number)) { return Double.NaN; }// w ww .j ava2 s . c o m double res = Math.floor((serial_number - Math.floor(serial_number)) * 86400 + 0.5); return Math.floor(res / 60) % 60; } public static final boolean isFinite(double x) { return !(Double.isInfinite(x) || Double.isNaN(x)); } }