diff --git a/iterator_adaptor_test.cpp b/iterator_adaptor_test.cpp index 6a300a6..3bc6b96 100644 --- a/iterator_adaptor_test.cpp +++ b/iterator_adaptor_test.cpp @@ -416,10 +416,10 @@ main() static const int index_size = 4; element_range_type elements( element_range_size ); - for(element_range_type::iterator it = elements.begin(); it != elements.end(); ++it ) *it = std::distance( elements.begin(), it ); + for(element_range_type::iterator el_it = elements.begin(); el_it != elements.end(); ++el_it ) *el_it = std::distance( elements.begin(), el_it ); index_type indices( index_size ); - std::iota( indices.begin(), indices.end(), element_range_size - index_size ); + for(index_type::iterator i_it = indices.begin() ; i_it != indices.end() ; ++i_it ) *i_it = element_range_size - index_size + std::distance(indices.begin(), i_it ); std::reverse( indices.begin(), indices.end() ); typedef boost::permutation_iterator_generator< element_range_type::iterator, index_type::iterator >::type permutation_type; diff --git a/permutation_iterator.htm b/permutation_iterator.htm index fc19d23..a0a2546 100644 --- a/permutation_iterator.htm +++ b/permutation_iterator.htm @@ -115,6 +115,9 @@ make_permutation_iterator(ElementIterator& base, IndexIterator& order);

Example

+  using namespace boost;
+  int i = 0;
+
   typedef std::vector< int > element_range_type;
   typedef std::list< int > index_type;
 
@@ -122,10 +125,10 @@ make_permutation_iterator(ElementIterator& base, IndexIterator& order);
   static const int index_size = 4;
 
   element_range_type elements( element_range_size );
-  std::iota( elements.begin(), elements.end(), 0 );
+  for(element_range_type::iterator el_it = elements.begin() ; el_it != elements.end() ; ++el_it) *el_it = std::distance(elements.begin(), el_it);
 
   index_type indices( index_size );
-  std::iota( indices.begin(), indices.end(), element_range_size - index_size );
+  for(index_type::iterator i_it = indices.begin() ; i_it != indices.end() ; ++i_it ) *i_it = element_range_size - index_size + std::distance(indices.begin(), i_it);
   std::reverse( indices.begin(), indices.end() );
 
   typedef permutation_iterator_generator< element_range_type::iterator, index_type::iterator >::type permutation_type;
@@ -133,18 +136,33 @@ make_permutation_iterator(ElementIterator& base, IndexIterator& order);
   permutation_type it = begin;
   permutation_type end = make_permutation_iterator( elements.begin(), indices.end() );
 
-  std::cout.setf( std::ios_base::left );
-  std::cout << std::setw( 50 ) << "The original range is : ";
+  std::cout << "The original range is : ";
   std::copy( elements.begin(), elements.end(), std::ostream_iterator< int >( std::cout, " " ) );
   std::cout << "\n";
 
-  std::cout << std::setw( 50 ) << "The reindexing scheme is : ";
+  std::cout << "The reindexing scheme is : ";
   std::copy( indices.begin(), indices.end(), std::ostream_iterator< int >( std::cout, " " ) );
   std::cout << "\n";
 
-  std::cout << std::setw( 50 ) << "The permutated range is : ";
+  std::cout << "The permutated range is : ";
   std::copy( begin, end, std::ostream_iterator< int >( std::cout, " " ) );
   std::cout << "\n";
+
+  std::cout << "Elements at even indices in the permutation : ";
+  it = begin;
+  for(i = 0; i < index_size / 2 ; ++i, it+=2 ) std::cout << *it << " ";
+  std::cout << "\n";
+
+  std::cout << "Permutation backwards : ";
+  it = begin + (index_size);
+  assert( it != begin );
+  for( ; it-- != begin ; ) std::cout << *it << " ";
+  std::cout << "\n";
+
+  std::cout << "Iterate backward with stride 2 : ";
+  it = begin + (index_size - 1);
+  for(i = 0 ; i < index_size / 2 ; ++i, it-=2 ) std::cout << *it << " ";
+  std::cout << "\n";