added: Big::Sqrt()

global algorithm ttmath::Sqrt() moved to Big::Sqrt()


git-svn-id: svn://ttmath.org/publicrep/ttmath/trunk@229 e52654a7-88a9-db11-a3e9-0013d4bc506e

ttmath/ttmath.h

@@ -1843,20 +1843,7 @@ namespace ttmath
 		return ValueType(); // NaN is set by default
 		}
 
-		if( x.IsZero() )
-		{
-			// Sqrt(0) = 0
-			if( err )
-				*err = err_ok;
-
-		return x;
-		}
-
-		ValueType pow;
-		pow.Set05();
-
-		// PowFrac can return only a carry because x is greater than zero
-		uint c = x.PowFrac(pow);
+		uint c = x.Sqrt();
 
 		if( err )
 			*err = c ? err_overflow : err_ok;

ttmath/ttmathbig.h

@@ -1509,6 +1509,33 @@ public:
 	}
 
 
+	/*!
+		this function calculates the square root
+
+		Sqrt(9) = 3
+
+		return: 0 - ok
+				1 - carry
+		        2 - improper argument (this<0 or NaN)
+	*/
+	uint Sqrt()
+	{
+		if( IsNan() || IsSign() )
+		{
+			SetNan();
+			return 2;
+		}
+
+		if( IsZero() )
+			return 0;
+
+		Big<exp, man> pow;
+		pow.Set05();
+
+	// PowFrac can return only a carry because x is greater than zero
+	return PowFrac(pow);
+	}
+
 
 private: