/***************************************************************************
                          ksutils.cpp  -  Trinity Desktop Planetarium
                             -------------------
    begin                : Mon Jan  7 10:48:09 EST 2002
    copyright            : (C) 2002 by Mark Hollomon
    email                : mhh@mindspring.com
 ***************************************************************************/

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

#include <kstandarddirs.h>
#include <tqfile.h>
#include "ksutils.h"

bool KSUtils::openDataFile( TQFile &file, const TQString &s ) {
	bool result;
	TQString FileName = locate( "appdata", s );

	if ( !FileName.isNull() ) {
		file.setName( FileName );
		if ( !file.open( IO_ReadOnly ) ) {
			result = false;
		} else {
			result = true;
		}
	} else {
		result = false;
	}

	return result;
}

long double KSUtils::lagrangeInterpolation( const long double x[], const long double v[], int n, long double xval) {
	long double value = 0;
	for (int i=1; i<n; ++i) {
		long double c = 1.0;
		for (int j = 1; j<n;++j) 
			if (i != j)
				c *= (xval - x[j]) / (x[i] - x[j]);
		value += c *v[i];
	}
	
	return value;
}