[Lemon-commits] ladanyi: r3335 - lemon/trunk/lemon

[Lemon SVN]

Author: ladanyi
Date: Sat Oct 13 10:48:07 2007
New Revision: 3335

Modified:
   lemon/trunk/lemon/lp_base.h

Log:
Added the function isFinite(), and replaced the calls to finite() with it.
This was necessary because finite() is not a standard function. Neither can
we use its standard counterpart isfinite(), because it was introduced only
in C99, and therefore it is not supplied by all C++ implementations.


Modified: lemon/trunk/lemon/lp_base.h
==============================================================================
--- lemon/trunk/lemon/lp_base.h	(original)
+++ lemon/trunk/lemon/lp_base.h	Sat Oct 13 10:48:07 2007
@@ -35,6 +35,23 @@
 ///\ingroup lp_group
 namespace lemon {
 
+  /// Function to decide whether a floating point value is finite or not.
+
+  /// Retruns true if the argument is not infinity, minus infinity or NaN.
+  /// It does the same as the isfinite() function defined by C99.
+  template <typename T>
+  bool isFinite(T value)
+  {
+    typedef std::numeric_limits<T> Lim;
+    if (Lim::has_infinity && (value == Lim::infinity() || value ==
+          -Lim::infinity()) ||
+        (Lim::has_quiet_NaN || Lim::has_signaling_NaN) && value != value)
+    {
+      return false;
+    }
+    return true;
+  }
+
   ///Common base class for LP solvers
   
   ///\todo Much more docs
@@ -457,13 +474,11 @@
       const Value &upperBound() const { return _ub; }
       ///Is the constraint lower bounded?
       bool lowerBounded() const { 
-	using namespace std;
-	return finite(_lb);
+	return isFinite(_lb);
       }
       ///Is the constraint upper bounded?
       bool upperBounded() const {
-	using namespace std;
-	return finite(_ub);
+	return isFinite(_ub);
       }
 
       void prettyPrint(std::ostream &os) {