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// Copyright (c) 1995-2009 Nokia Corporation and/or its subsidiary(-ies).
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// All rights reserved.
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// This component and the accompanying materials are made available
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// under the terms of the License "Eclipse Public License v1.0"
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// which accompanies this distribution, and is available
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// at the URL "http://www.eclipse.org/legal/epl-v10.html".
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//
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// Initial Contributors:
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// Nokia Corporation - initial contribution.
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//
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// Contributors:
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//
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// Description:
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// e32\euser\maths\um_log.cpp
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// Floating point base 10 logarithm
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//
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//
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#include "um_std.h"
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#if defined(__USE_VFP_MATH) && !defined(__CPU_HAS_VFP)
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#error __USE_VFP_MATH was defined but not __CPU_HAS_VFP - impossible combination, check variant.mmh
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#endif
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#ifndef __USE_VFP_MATH
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EXPORT_C TInt Math::Log(TReal &aTrg,const TReal &aSrc)
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/**
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Calculates the logarithm to base 10 of a number.
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@param aTrg A reference containing the result.
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@param aSrc The number whose logarithm is required.
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@return KErrNone if successful, otherwise another of
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the system-wide error codes.
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*/
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//
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// Base 10 log routine. See Software manual by W.J.Cody & W.Waite
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//
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{
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TInt ret=Math::Ln(aTrg,aSrc);
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if (ret!=KErrNone)
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return(ret);
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aTrg*=KRln10;
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return(ret);
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}
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#else // __USE_VFP_MATH
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// definitions come from RVCT math library
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extern "C" TReal log10(TReal);
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EXPORT_C TInt Math::Log(TReal& aTrg, const TReal& aSrc)
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{
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aTrg = log10(aSrc);
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if (Math::IsFinite(aTrg))
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return KErrNone;
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if (Math::IsInfinite(aTrg))
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return KErrOverflow;
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SetNaN(aTrg);
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return KErrArgument;
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}
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#endif
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