Here you can find the source of atanD(final double arg)
static final public double atanD(final double arg)
//package com.java2s; //License from project: Apache License public class Main { static final public double atanD(final double arg) { // handle special cases first if (Double.POSITIVE_INFINITY == arg) return 90.0; else if (Double.NEGATIVE_INFINITY == arg) return -90.0; else//from w w w . j a v a 2 s .c o m return Math.toDegrees(Math.atan(arg)); } }