//
// PolarCoordinateSystem.java
//

/*
VisAD system for interactive analysis and visualization of numerical
data.  Copyright (C) 1996 - 2017 Bill Hibbard, Curtis Rueden, Tom
Rink, Dave Glowacki, Steve Emmerson, Tom Whittaker, Don Murray, and
Tommy Jasmin.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA
*/

package visad;

/**
   PolarCoordinateSystem is the VisAD CoordinateSystem class
   for (Longitude, Radius) with a Cartesian Reference,
   and with Longitude in degrees.

*/
public class PolarCoordinateSystem extends CoordinateSystem {

  private static Unit[] coordinate_system_units =
    {CommonUnit.degree, null};

  /** construct a CoordinateSystem for (longitude, radius)
      relative to a 2-D Cartesian reference;
      this constructor supplies units = {CommonUnit.Degree, null}
      to the super constructor, in order to ensure Unit
      compatibility with its use of trigonometric functions */
  public PolarCoordinateSystem(RealTupleType reference)
         throws VisADException {
    super(reference, coordinate_system_units);
  }

  public double[][] toReference(double[][] tuples) throws VisADException {
    if (tuples == null || tuples.length != 2) {
      throw new CoordinateSystemException("PolarCoordinateSystem." +
             "toReference: tuples wrong dimension");
    }
    int len = tuples[0].length;
    double[][] value = new double[2][len];
    for (int i=0; i