/**
* Copyright (C) 2009, 2010 SC 4ViewSoft SRL
*
* 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 org.achartengine.util;
import java.text.NumberFormat;
import java.util.List;
/**
* Utility class for math operations.
*/
class MathHelper {
/** A value that is used a null value. */
public static final double NULL_VALUE = Double.MAX_VALUE;
/**
* A number formatter to be used to make sure we have a maximum number of
* fraction digits in the labels.
*/
private static final NumberFormat FORMAT = NumberFormat.getNumberInstance();
private MathHelper() {
// empty constructor
}
/**
* Given a number, round up to the nearest power of ten times 1, 2, or 5. The
* argument must be strictly positive.
*/
private static double roundUp(final double val) {
int exponent = (int) Math.floor(Math.log10(val));
double rval = val * Math.pow(10, -exponent);
if (rval > 5.0) {
rval = 10.0;
} else if (rval > 2.0) {
rval = 5.0;
} else if (rval > 1.0) {
rval = 2.0;
}
rval *= Math.pow(10, exponent);
return rval;
}
}