From 5c554bd7bc7b03d62fb566be5c1286b678598d95 Mon Sep 17 00:00:00 2001
From: William Dawson <william.dawson@riken.jp>
Date: Thu, 18 Apr 2024 11:30:32 +0900
Subject: [PATCH] forgot a file

---
 .../triplet_includes/GatherTripletList.f90    | 66 +++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 Source/Fortran/triplet_includes/GatherTripletList.f90

diff --git a/Source/Fortran/triplet_includes/GatherTripletList.f90 b/Source/Fortran/triplet_includes/GatherTripletList.f90
new file mode 100644
index 00000000..2c19518f
--- /dev/null
+++ b/Source/Fortran/triplet_includes/GatherTripletList.f90
@@ -0,0 +1,66 @@
+!! Local Data - Send/Recv Buffers
+INTEGER, DIMENSION(:), ALLOCATABLE :: send_buffer_row
+INTEGER, DIMENSION(:), ALLOCATABLE :: send_buffer_col
+INTEGER, DIMENSION(:), ALLOCATABLE :: recv_buffer_row
+INTEGER, DIMENSION(:), ALLOCATABLE :: recv_buffer_col
+
+!! Sizes help
+INTEGER, DIMENSION(:), ALLOCATABLE :: recvcounts
+INTEGER, DIMENSION(:), ALLOCATABLE :: displ
+INTEGER :: gather_size
+
+!! Temporary variables
+INTEGER :: num_processes, II, ierr
+
+!! Figure out the comm size
+CALL MPI_COMM_SIZE(comm, num_processes, ierr)
+
+!! Get the count 
+ALLOCATE(recvcounts(num_processes))
+CALL MPI_Allgather(triplet_in%CurrentSize, 1, MPI_INTEGER, recvcounts, &
+     & 1, MPI_INTEGER, comm, ierr)
+
+!! Get the displacements
+gather_size = SUM(recvcounts)
+ALLOCATE(displ(num_processes))
+displ(1) = 0
+DO II = 2, num_processes
+  displ(II) = displ(II - 1) + recvcounts(II - 1)
+END DO
+
+!! Prepare the send buffers
+ALLOCATE(send_buffer_row(triplet_in%CurrentSize))
+ALLOCATE(send_buffer_col(triplet_in%CurrentSize))
+ALLOCATE(send_buffer_val(triplet_in%CurrentSize))
+DO II = 1, triplet_in%CurrentSize
+   CALL GetTripletAt(triplet_in, II, temp_triplet)
+   send_buffer_row(II) = temp_triplet%index_row
+   send_buffer_col(II) = temp_triplet%index_column
+   send_buffer_val(II) = temp_triplet%point_value
+END DO
+
+!! Gather Call
+ALLOCATE(recv_buffer_row(gather_size))
+ALLOCATE(recv_buffer_col(gather_size))
+ALLOCATE(recv_buffer_val(gather_size))
+CALL MPI_Allgatherv(send_buffer_row, triplet_in%CurrentSize, MPI_INTEGER, &
+     & recv_buffer_row, recvcounts, displ, MPI_INTEGER, comm, ierr)
+CALL MPI_Allgatherv(send_buffer_col, triplet_in%CurrentSize, MPI_INTEGER, &
+     & recv_buffer_col, recvcounts, displ, MPI_INTEGER, comm, ierr)
+CALL MPI_Allgatherv(send_buffer_val, triplet_in%CurrentSize, MPIDATATYPE, &
+     & recv_buffer_val, recvcounts, displ, MPIDATATYPE, comm, ierr)
+
+!! Unpack
+CALL ConstructTripletList(gathered_out, gather_size)
+DO II = 1, gather_size
+   gathered_out%DATA(II)%index_row = recv_buffer_row(II)
+   gathered_out%DATA(II)%index_column = recv_buffer_col(II)
+   gathered_out%DATA(II)%point_value = recv_buffer_val(II)
+END DO
+
+!! Cleanup
+DEALLOCATE(recvcounts)
+DEALLOCATE(displ)
+DEALLOCATE(send_buffer_row)
+DEALLOCATE(send_buffer_col)
+DEALLOCATE(send_buffer_val)