--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symport/e32/euser/maths/um_sqrt.cpp	Thu Jun 25 15:59:54 2009 +0100
@@ -0,0 +1,90 @@
+// 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 "Symbian Foundation License v1.0"
+// which accompanies this distribution, and is available
+// at the URL "http://www.symbianfoundation.org/legal/sfl-v10.html".
+//
+// Initial Contributors:
+// Nokia Corporation - initial contribution.
+//
+// Contributors:
+//
+// Description:
+// e32\euser\maths\um_sqrt.cpp
+// Square root.
+// 
+//
+
+#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
+
+#ifndef __REALS_MACHINE_CODED__
+LOCAL_D const TUint32 KConstAdata[] = {0x00000000,0xD5A9A805,0x7FFD0000};
+LOCAL_D const TUint32 KConstBdata[] = {0x00000000,0x9714B9CB,0x7FFE0000};
+LOCAL_D const TUint32 Sqr2Invdata[] = {0xF9DE6484,0xB504F333,0x7FFE0000};		// 1/sqr2
+
+
+
+
+EXPORT_C TInt Math::Sqrt(TReal& aTrg,const TReal &aSrc)
+/**
+Calculates the square root of a number.
+
+@param aTrg A reference containing the result. 
+@param aSrc The number whose square-root is required.
+
+@return KErrNone if successful, otherwise another of
+        the system-wide error codes. 
+*/
+//
+// Fast sqrt routine. See Software manual by W.J.Cody & W.Waite Chapter 4.
+//
+	{
+	const TRealX& KConstA=*(const TRealX*)KConstAdata;
+	const TRealX& KConstB=*(const TRealX*)KConstBdata;
+	const TRealX& Sqr2Inv=*(const TRealX*)Sqr2Invdata;
+
+	TRealX x;
+	TInt r=x.Set(aSrc);
+	if (x.IsZero())
+		{
+		aTrg=aSrc;
+		return(KErrNone);
+		}   
+	if (r==KErrArgument || x.iSign&1)
+		{
+		SetNaN(aTrg);
+		return(KErrArgument);
+		}
+	if (r==KErrOverflow)	// positive infinity
+		{
+		aTrg=aSrc;
+		return(r);
+		}
+	TInt n=x.iExp-0x7FFE;
+	x.iExp=0x7FFE;
+	TRealX y=KConstB*x+KConstA;
+	y=y+(x/y);
+	y.iExp--;
+	y=y+(x/y);
+	y.iExp--;
+	y=y+(x/y);
+	y.iExp--;
+	if (n&1)
+		{
+		y*=Sqr2Inv;
+		n++;
+		}
+	y.iExp=TUint16(TInt(y.iExp)+(n>>1));
+	return y.GetTReal(aTrg);
+	}
+#endif
+
+#endif // !__USE_VFP_MATH - VFP version is in assembler