// Copyright (c) 1995-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of the License "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

// at the URL "http://www.eclipse.org/legal/epl-v10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

// e32\euser\maths\um_log.cpp

// Floating point base 10 logarithm

// 

//

#include "um_std.h"

#if defined(__USE_VFP_MATH) && !defined(__CPU_HAS_VFP)

#error	__USE_VFP_MATH was defined but not __CPU_HAS_VFP - impossible combination, check variant.mmh 

#endif

#ifndef __USE_VFP_MATH

EXPORT_C TInt Math::Log(TReal &aTrg,const TReal &aSrc)

/**

Calculates the logarithm to base 10 of a number.

@param aTrg  A reference containing the result. 

@param aSrc  The number whose logarithm is required. 

@return KErrNone if successful, otherwise another of

        the system-wide error codes. 

*/

//

// Base 10 log routine. See Software manual by W.J.Cody & W.Waite

//

	{

	TInt ret=Math::Ln(aTrg,aSrc);

	if (ret!=KErrNone)

		return(ret);    	

	aTrg*=KRln10;

	return(ret);

	}

#else // __USE_VFP_MATH

// definitions come from RVCT math library

extern "C" TReal log10(TReal);

EXPORT_C TInt Math::Log(TReal& aTrg, const TReal& aSrc)

	{

	aTrg = log10(aSrc);

	if (Math::IsFinite(aTrg))

		return KErrNone;

	if (Math::IsInfinite(aTrg))

		return KErrOverflow;

	SetNaN(aTrg);

	return KErrArgument;

	}

#endif