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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_mod.cpp
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// Writes the remainder of aSrc/aModulus to aTrg
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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::Mod(TReal &aTrg,const TReal &aSrc,const TReal &aModulus)
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/**
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Calculates the modulo remainder.
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This is the value of p mod q, the modulo remainder when dividing p by q.
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The result is given by p - q int (p/q):
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it has the same sign as p:
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thus, 5 mod 3 = 2, -5 mod 3 = -2.
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No error is raised if non-integer arguments are passed.
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@param aTrg A reference containing the result.
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@param aSrc The p argument to the mod function.
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@param aModulus The q argument to the mod function.
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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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// Floating point modulo arithmetic.
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//
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{
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TRealX f1,f2;
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TInt r=f1.Set(aSrc);
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if (r!=KErrNone)
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{
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SetNaN(aTrg);
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return KErrArgument;
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}
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r=f2.Set(aModulus);
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if (r==KErrArgument || f2.IsZero())
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{
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SetNaN(aTrg);
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return KErrArgument;
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}
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if (r==KErrOverflow)
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{
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aTrg=aSrc;
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return KErrNone;
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}
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if ((TInt(f1.iExp)-TInt(f2.iExp))>KMantissaBits)
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{
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SetZero(aTrg);
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return KErrTotalLossOfPrecision;
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}
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f1.ModEq(f2);
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return f1.GetTReal(aTrg);
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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 fmod(TReal,TReal);
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EXPORT_C TInt Math::Mod(TReal& aTrg, const TReal& aSrc, const TReal &aModulus)
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{
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SReal64 *pSrc=(SReal64 *)&aSrc;
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SReal64 *pModulus=(SReal64 *)&aModulus;
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if (pSrc->exp==0 || pModulus->exp==0 || pSrc->exp==KSpecialExponent || pModulus->exp==KSpecialExponent)
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{
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TRealX f1,f2;
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TInt r=f1.Set(aSrc);
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if (r!=KErrNone)
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{
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SetNaN(aTrg);
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return KErrArgument;
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}
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r=f2.Set(aModulus);
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if (r==KErrArgument || f2.IsZero())
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{
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SetNaN(aTrg);
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return KErrArgument;
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}
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if (r==KErrOverflow)
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{
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aTrg=aSrc;
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return KErrNone;
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}
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if ((TInt(f1.iExp)-TInt(f2.iExp))>KMantissaBits)
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{
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SetZero(aTrg);
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return KErrTotalLossOfPrecision;
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}
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}
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else if ((pSrc->exp - pModulus->exp) > KMantissaBits)
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{
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SetZero(aTrg);
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return KErrTotalLossOfPrecision;
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}
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aTrg = fmod(aSrc,aModulus);
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return KErrNone;
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}
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#endif
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