Writting documentation on CSR format.

Documentation/Examples/Algorithms/Segments/CMakeLists.txt

@@ -5,6 +5,7 @@ set( COMMON_EXAMPLES
    SegmentsExample_CSR_getSerializationType
    SegmentsExample_CSR_getSegmentsType
    SegmentsExample_CSR_setSegmentsSizes
+   SegmentsExample_CSR_getSegmentView
 )
 
 if( BUILD_CUDA )

Documentation/Examples/Algorithms/Segments/SegmentsExample_CSR_getSegmentView.cpp

+#include <iostream>
+#include <functional>
+#include <TNL/Containers/Vector.h>
+#include <TNL/Algorithms/Segments/CSR.h>
+#include <TNL/Algorithms/SequentialFor.h>
+#include <TNL/Devices/Host.h>
+#include <TNL/Devices/Cuda.h>
+
+template< typename Device >
+void SegmentsExample()
+{
+   using SegmentsType = typename TNL::Algorithms::Segments::CSR< Device, int >;
+   using SegmentView = typename SegmentsType::SegmentViewType;
+
+   /***
+    * Create segments with given segments sizes.
+    */
+   const int size( 5 );
+   SegmentsType segments{ 1, 2, 3, 4, 5 };
+   auto view = segments.getView();
+
+   /***
+    * Print the elemets mapping using segment view.
+    */
+   std::cout << "Mapping of local indexes to global indexes:" << std::endl;
+
+   auto f = [=] __cuda_callable__ ( int segmentIdx ) {
+      printf( "Segment idx. %d: ", segmentIdx );                 // printf works even in GPU kernels
+      auto segment = view.getSegmentView( segmentIdx );
+      for( auto element : segment )
+         printf( "%d -> %d \t", element.localIndex(), element.globalIndex() );
+      printf( "\n" );
+   };
+   TNL::Algorithms::SequentialFor< Device >::exec( 0, size, f );
+}
+
+int main( int argc, char* argv[] )
+{
+   std::cout << "Example of CSR segments on host: " << std::endl;
+   SegmentsExample< TNL::Devices::Host >();
+
+#ifdef HAVE_CUDA
+   std::cout << "Example of CSR segments on CUDA GPU: " << std::endl;
+   SegmentsExample< TNL::Devices::Cuda >();
+#endif
+   return EXIT_SUCCESS;
+}

Documentation/Examples/Algorithms/Segments/SegmentsExample_CSR_getSegmentView.cu

+SegmentsExample_CSR_getSegmentView.cpp
\ No newline at end of file

Documentation/Examples/Algorithms/Segments/SegmentsExample_CSR_getSegmentsType.cu

+SegmentsExample_CSR_getSegmentsType.cpp
\ No newline at end of file

Documentation/Examples/Algorithms/Segments/SegmentsExample_CSR_sequentialForAllSegments.cpp

+#include <iostream>
+#include <functional>
+#include <TNL/Containers/Vector.h>
+#include <TNL/Algorithms/Segments/CSR.h>
+#include <TNL/Devices/Host.h>
+#include <TNL/Devices/Cuda.h>
+
+template< typename Device >
+void SegmentsExample()
+{
+   using SegmentsType = typename TNL::Algorithms::Segments::CSR< Device, int >;
+   using SegmentViewType = typename SegmentsType::SegmentView;
+
+   /***
+    * Create segments with given segments sizes.
+    */
+   SegmentsType segments{ 1, 2, 3, 4, 5 };
+   std::cout << "Segments sizes are: " << segments << std::endl;
+
+   /***
+    * Print the elemets mapping using segment view.
+    */
+   std::cout << "Elements mapping:" << std::endl;
+   segments.sequentialForAllSegments( [] __cuda_callable__ ( const SegmentView segment ) {
+      printf( "Segment idx. %d: \n", segments.getSegmentIndex() );                 // printf works even in GPU kernels
+      for( auto element : segment )
+         printf( "%d -> %d  ", element.localIndex(), element.globalIndex() );
+   } );
+
+}
+
+int main( int argc, char* argv[] )
+{
+   std::cout << "Example of CSR segments on host: " << std::endl;
+   SegmentsExample< TNL::Devices::Host >();
+
+#ifdef HAVE_CUDA
+   std::cout << "Example of CSR segments on CUDA GPU: " << std::endl;
+   SegmentsExample< TNL::Devices::Cuda >();
+#endif
+   return EXIT_SUCCESS;
+}

src/TNL/Algorithms/Segments/CSR.h

@@ -270,12 +270,27 @@ class CSR
        *
        * \param segmentIdx is index of the request segment.
        * \return segment view of given segment.
+       *
+       * \par Example
+       * \include Algorithms/Segments/SegmentsExample_CSR_getSegmentView.cpp
+       * \par Output
+       * \include SegmentsExample_CSR_getSegmentView.out
        */
       __cuda_callable__
       SegmentViewType getSegmentView( const IndexType segmentIdx ) const;
 
+      /**
+       * \brief Returns reference on constant vector with row offsets used in the CSR format.
+       *
+       * \return reference on constant vector with row offsets used in the CSR format.
+       */
       const OffsetsContainer& getOffsets() const;
 
+      /**
+       * \brief Returns reference on vector with row offsets used in the CSR format.
+       *
+       * \return reference on vector with row offsets used in the CSR format.
+       */
       OffsetsContainer& getOffsets();
 
       /***
@@ -296,6 +311,13 @@ class CSR
       template< typename Function >
       void forAllSegments( Function&& f ) const;
 
+      template< typename Function >
+      void sequentialForSegments( IndexType begin, IndexType end, Function&& f ) const;
+
+      template< typename Function >
+      void sequentialForAllSegments( Function&& f ) const;
+
+
       /***
        * \brief Go over all segments and perform a reduction in each of them.
        */

src/TNL/Algorithms/Segments/CSR.hpp

@@ -283,6 +283,30 @@ forAllSegments( Function&& f ) const
    this->getConstView().forAllSegments( f );
 }
 
+template< typename Device,
+          typename Index,
+          typename Kernel,
+          typename IndexAllocator >
+   template< typename Function >
+void
+CSR< Device, Index, Kernel, IndexAllocator >::
+sequentialForSegments( IndexType begin, IndexType end, Function&& f ) const
+{
+   this->getConstView().sequentialForSegments( begin, end, f );
+}
+
+template< typename Device,
+          typename Index,
+          typename Kernel,
+          typename IndexAllocator >
+   template< typename Function >
+void
+CSR< Device, Index, Kernel, IndexAllocator >::
+sequentialForAllSegments( Function&& f ) const
+{
+   this->getConstView().sequentialForAllSegments( f );
+}
+
 template< typename Device,
           typename Index,
           typename Kernel,

src/TNL/Algorithms/Segments/CSRView.h

@@ -118,6 +118,12 @@ class CSRView
       template< typename Function >
       void forAllSegments( Function&& f ) const;
 
+      template< typename Function >
+      void sequentialForSegments( IndexType begin, IndexType end, Function&& f ) const;
+
+      template< typename Function >
+      void sequentialForAllSegments( Function&& f ) const;
+
       /***
        * \brief Go over all segments and perform a reduction in each of them.
        */

src/TNL/Algorithms/Segments/CSRView.hpp

@@ -238,6 +238,29 @@ forAllSegments( Function&& f ) const
    this->forSegments( 0, this->getSegmentsCount(), f );
 }
 
+template< typename Device,
+          typename Index,
+          typename Kernel >
+   template< typename Function >
+void
+CSRView< Device, Index, Kernel >::
+sequentialForSegments( IndexType begin, IndexType end, Function&& function ) const
+{
+   for( IndexType i = begin; i < end; i++ )
+      forSegments( i, i + 1, function );
+}
+
+template< typename Device,
+          typename Index,
+          typename Kernel >
+   template< typename Function >
+void
+CSRView< Device, Index, Kernel >::
+sequentialForAllSegments( Function&& f ) const
+{
+   this->sequentialForSegments( 0, this->getSegmentsCount(), f );
+}
+
 template< typename Device,
           typename Index,
           typename Kernel >