Changeset 1789 for trunk/yat/utility/utility.h

Timestamp:

Feb 10, 2009, 5:11:04 PM (12 years ago)

Author:

Peter

Message:

Speeding up copying from Matrix to MatrixWeighted? using
BinaryWeight?. Moving BinaryWeight? from stl_utility.h to
utility.h. Improved docs in MatrixWeighted?.

File:

• trunk/yat/utility/utility.h (modified) (3 diffs)

trunk/yat/utility/utility.h

@@ -34 +34 @@
 #include "deprecate.h"
 
+#include <cmath>
 #include <limits>
 #include <string>
@@ -45 +46 @@
 namespace utility {
 
-  class Matrix;
+  /**
+     For each element in resulting range assign it to 0.0 if
+     corresponding element in input range is NaN else assign it to
+     1.0.
+
+     \since New in yat 0.5
+   */
+  struct BinaryWeight
+  {
+    /** 
+        \return true if there is at least one NaN in input range
+        [first, last).
+     */
+    template<typename InputIterator, typename OutputIterator>
+    bool operator()(InputIterator first, InputIterator last, 
+                    OutputIterator result) const;
+  };
+
 
   /**
@@ -99 +117 @@
   bool is_nan(const std::string& s);
 
+
+  template<typename InputIterator, typename OutputIterator>
+  bool BinaryWeight::operator()(InputIterator first, InputIterator last, 
+                                OutputIterator result) const
+  {
+    bool nan=false;
+    while (first!=last) {
+      if (std::isnan(*first)) {
+        *result=0;
+        nan=true;
+      }
+      else
+        *result = 1.0;
+      ++first;
+      ++result;
+    }
+    return nan;
+  }
+
+
   // template implementations
   template<typename T>