init_AliasSampler_t Subroutine

private subroutine init_AliasSampler_t(this, rank_with_info, arr)

load the probability distribution from arr into this we only use this in the sampler array, but fortran has no friend classes, so its public want to use for sampling

Type Bound

AliasSampler_t

Arguments

Type IntentOptional Attributes Name
class(AliasSampler_t), intent(inout) :: this
integer, intent(in) :: rank_with_info

The intra-node rank that contains the weights to be used all other arr of all other ranks are ignored (and can be allocated with size 0).
real(kind=dp), intent(in) :: arr(:)

Source Code

    subroutine init_AliasSampler_t(this, rank_with_info, arr)
        class(AliasSampler_t), intent(inout) :: this
        integer, intent(in) :: rank_with_info
            !! The **intra-node** rank that contains the weights to be used
            !! all other arr of all other ranks are ignored (and can be allocated with size 0).
        real(dp), intent(in) :: arr(:)

        block
            logical :: early_return(1)
            integer :: ierr
            early_return = near_zero(sum(arr))
            call MPI_Bcast(early_return, size(early_return, kind=MPIArg), MPI_LOGICAL, rank_with_info, mpi_comm_intra, ierr)

            if (early_return(1)) then
                ! if we reach this point, probs is uninitialized -> null it
                this%probs%ptr => null()
                return
            end if
        end block

        ! load the data - assume this is pre-allocated
        call this%table%init(rank_with_info, arr)
        call this%init_probs(rank_with_info, arr)
    end subroutine init_AliasSampler_t