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psblas3/base/psblas/psb_snrm2.f90

727 lines
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!
! Parallel Sparse BLAS version 3.5
! (C) Copyright 2006-2018
! Salvatore Filippone
! Alfredo Buttari
!
! Redistribution and use in source and binary forms, with or without
! modification, are permitted provided that the following conditions
! are met:
! 1. Redistributions of source code must retain the above copyright
! notice, this list of conditions and the following disclaimer.
! 2. Redistributions in binary form must reproduce the above copyright
! notice, this list of conditions, and the following disclaimer in the
! documentation and/or other materials provided with the distribution.
! 3. The name of the PSBLAS group or the names of its contributors may
! not be used to endorse or promote products derived from this
! software without specific written permission.
!
! THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
! ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
! TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
! PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PSBLAS GROUP OR ITS CONTRIBUTORS
! BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
! CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
! SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
! INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
! CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
! ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
! POSSIBILITY OF SUCH DAMAGE.
!
!
! File: psb_snrm2.f90
!
! Function: psb_snrm2
! Computes the norm2 of a distributed vector,
!
! norm2 := sqrt ( sub( X )**C * sub( X ) )
!
! where sub( X ) denotes X(:,JX).
!
! Arguments:
! x(:,:) - real The input vector containing the entries of sub( X ).
! desc_a - type(psb_desc_type). The communication descriptor.
! info - integer. Return code
! jx - integer(optional). The column offset for sub( X ).
! global - logical(optional) Whether to perform the global reduction, default: .true.
!
function psb_snrm2(x, desc_a, info, jx,global) result(res)
use psb_desc_mod
use psb_check_mod
use psb_error_mod
use psb_penv_mod
implicit none
real(psb_spk_), intent(in) :: x(:,:)
type(psb_desc_type), intent(in) :: desc_a
integer(psb_ipk_), intent(in), optional :: jx
integer(psb_ipk_), intent(out) :: info
real(psb_spk_) :: res
logical, intent(in), optional :: global
! locals
type(psb_ctxt_type) :: ctxt
integer(psb_ipk_) :: np, me,&
& err_act, iix, jjx, ndim, i, id, idx, ndm, ldx
integer(psb_lpk_) :: ix, ijx, iy, ijy, m
logical :: global_
real(psb_spk_) :: snrm2, dd
character(len=20) :: name, ch_err
name='psb_snrm2'
info=psb_success_
call psb_erractionsave(err_act)
if (psb_errstatus_fatal()) then
info = psb_err_internal_error_ ; goto 9999
end if
ctxt=desc_a%get_context()
call psb_info(ctxt, me, np)
if (np == -1) then
info=psb_err_context_error_
call psb_errpush(info,name)
goto 9999
endif
ix = 1
if (present(jx)) then
ijx = jx
else
ijx = 1
endif
if (present(global)) then
global_ = global
else
global_ = .true.
end if
m = desc_a%get_global_rows()
ldx = size(x,1)
call psb_chkvect(m,lone,ldx,ix,ijx,desc_a,info,iix,jjx)
if(info /= psb_success_) then
info=psb_err_from_subroutine_
ch_err='psb_chkvect'
call psb_errpush(info,name,a_err=ch_err)
end if
if (iix /= 1) then
info=psb_err_ix_n1_iy_n1_unsupported_
call psb_errpush(info,name)
goto 9999
end if
if (desc_a%get_local_rows() > 0) then
ndim = desc_a%get_local_rows()
res = snrm2( int(ndim,kind=psb_mpk_), x(iix:,jjx), int(ione,kind=psb_mpk_) )
! adjust because overlapped elements are computed more than once
do i=1,size(desc_a%ovrlap_elem,1)
idx = desc_a%ovrlap_elem(i,1)
ndm = desc_a%ovrlap_elem(i,2)
dd = real(ndm-1)/real(ndm)
res = res * sqrt(sone - dd*(abs(x(idx,jjx))/res)**2)
end do
else
res = szero
end if
if (global_) call psb_nrm2(ctxt,res)
call psb_erractionrestore(err_act)
return
9999 call psb_error_handler(ctxt,err_act)
return
end function psb_snrm2
!!$
!!$ Parallel Sparse BLAS version 3.5
!!$ (C) Copyright 2006-2018
!!$ Salvatore Filippone University of Rome Tor Vergata
!!$ Alfredo Buttari
!!$
!!$ Redistribution and use in source and binary forms, with or without
!!$ modification, are permitted provided that the following conditions
!!$ are met:
!!$ 1. Redistributions of source code must retain the above copyright
!!$ notice, this list of conditions and the following disclaimer.
!!$ 2. Redistributions in binary form must reproduce the above copyright
!!$ notice, this list of conditions, and the following disclaimer in the
!!$ documentation and/or other materials provided with the distribution.
!!$ 3. The name of the PSBLAS group or the names of its contributors may
!!$ not be used to endorse or promote products derived from this
!!$ software without specific written permission.
!!$
!!$ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
!!$ ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
!!$ TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
!!$ PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PSBLAS GROUP OR ITS CONTRIBUTORS
!!$ BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
!!$ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
!!$ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
!!$ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
!!$ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
!!$ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
!!$ POSSIBILITY OF SUCH DAMAGE.
!!$
!!$
!
! Function: psb_snrm2
! Computes the norm2 of a distributed vector,
!
! norm2 := sqrt ( X**C * X)
!
! Arguments:
! x(:) - real The input vector containing the entries of X.
! desc_a - type(psb_desc_type). The communication descriptor.
! info - integer. Return code
! global - logical(optional) Whether to perform the global reduction, default: .true.
!
function psb_snrm2v(x, desc_a, info,global) result(res)
use psb_desc_mod
use psb_check_mod
use psb_error_mod
use psb_penv_mod
implicit none
real(psb_spk_), intent(in) :: x(:)
type(psb_desc_type), intent(in) :: desc_a
integer(psb_ipk_), intent(out) :: info
real(psb_spk_) :: res
logical, intent(in), optional :: global
! locals
type(psb_ctxt_type) :: ctxt
integer(psb_ipk_) :: np, me,&
& err_act, iix, jjx, ndim, i, id, idx, ndm, ldx
integer(psb_lpk_) :: ix, jx, iy, ijy, m
real(psb_spk_) :: snrm2, dd
logical :: global_
character(len=20) :: name, ch_err
name='psb_snrm2v'
info=psb_success_
call psb_erractionsave(err_act)
if (psb_errstatus_fatal()) then
info = psb_err_internal_error_ ; goto 9999
end if
ctxt=desc_a%get_context()
call psb_info(ctxt, me, np)
if (np == -1) then
info=psb_err_context_error_
call psb_errpush(info,name)
goto 9999
endif
if (present(global)) then
global_ = global
else
global_ = .true.
end if
ix = 1
jx=1
m = desc_a%get_global_rows()
ldx = size(x,1)
call psb_chkvect(m,lone,ldx,ix,jx,desc_a,info,iix,jjx)
if(info /= psb_success_) then
info=psb_err_from_subroutine_
ch_err='psb_chkvect'
call psb_errpush(info,name,a_err=ch_err)
end if
if (iix /= 1) then
info=psb_err_ix_n1_iy_n1_unsupported_
call psb_errpush(info,name)
goto 9999
end if
if (desc_a%get_local_rows() > 0) then
ndim = desc_a%get_local_rows()
res = snrm2( int(ndim,kind=psb_mpk_), x, int(ione,kind=psb_mpk_) )
! adjust because overlapped elements are computed more than once
do i=1,size(desc_a%ovrlap_elem,1)
idx = desc_a%ovrlap_elem(i,1)
ndm = desc_a%ovrlap_elem(i,2)
dd = real(ndm-1)/real(ndm)
res = res * sqrt(sone - dd*(abs(x(idx))/res)**2)
end do
else
res = szero
end if
if (global_) call psb_nrm2(ctxt,res)
call psb_erractionrestore(err_act)
return
9999 call psb_error_handler(ctxt,err_act)
return
end function psb_snrm2v
! Function: psb_snrm2_vect
! Computes the norm2 of a distributed vector,
!
! norm2 := sqrt ( X**C * X)
!
! Arguments:
! x - type(psb_s_vect_type) The input vector containing the entries of X.
! desc_a - type(psb_desc_type). The communication descriptor.
! info - integer. Return code
! global - logical(optional) Whether to perform the global reduction, default: .true.
!
function psb_snrm2_vect(x, desc_a, info,global) result(res)
use psb_desc_mod
use psb_check_mod
use psb_error_mod
use psb_penv_mod
use psb_s_vect_mod
implicit none
real(psb_spk_) :: res
type(psb_s_vect_type), intent (inout) :: x
type(psb_desc_type), intent(in) :: desc_a
integer(psb_ipk_), intent(out) :: info
logical, intent(in), optional :: global
! locals
type(psb_ctxt_type) :: ctxt
integer(psb_ipk_) :: np, me,&
& err_act, iix, jjx, ndim, i, id, idx, ndm, ldx
integer(psb_lpk_) :: ix, jx, iy, ijy, m
logical :: global_
real(psb_spk_) :: snrm2, dd
character(len=20) :: name, ch_err
name='psb_snrm2v'
call psb_erractionsave(err_act)
if (psb_errstatus_fatal()) then
info = psb_err_internal_error_ ; goto 9999
end if
info=psb_success_
ctxt=desc_a%get_context()
call psb_info(ctxt, me, np)
if (np == -1) then
info=psb_err_context_error_
call psb_errpush(info,name)
goto 9999
endif
if (.not.allocated(x%v)) then
info = psb_err_invalid_vect_state_
call psb_errpush(info,name)
goto 9999
endif
if (present(global)) then
global_ = global
else
global_ = .true.
end if
ix = 1
jx = 1
m = desc_a%get_global_rows()
ldx = x%get_nrows()
call psb_chkvect(m,lone,ldx,ix,jx,desc_a,info,iix,jjx)
if(info /= psb_success_) then
info=psb_err_from_subroutine_
ch_err='psb_chkvect'
call psb_errpush(info,name,a_err=ch_err)
end if
if (iix /= 1) then
info=psb_err_ix_n1_iy_n1_unsupported_
call psb_errpush(info,name)
goto 9999
end if
if (desc_a%get_local_rows() > 0) then
ndim = desc_a%get_local_rows()
res = x%nrm2(ndim)
! adjust because overlapped elements are computed more than once
if (size(desc_a%ovrlap_elem,1)>0) then
if (x%is_dev()) call x%sync()
do i=1,size(desc_a%ovrlap_elem,1)
idx = desc_a%ovrlap_elem(i,1)
ndm = desc_a%ovrlap_elem(i,2)
dd = dble(ndm-1)/dble(ndm)
res = res * sqrt(sone - dd*(abs(x%v%v(idx))/res)**2)
end do
end if
else
res = szero
end if
if (global_) call psb_nrm2(ctxt,res)
call psb_erractionrestore(err_act)
return
9999 call psb_error_handler(ctxt,err_act)
return
end function psb_snrm2_vect
! Function: psb_snrm2_weight_vect
! Computes the weighted norm2 of a distributed vector,
!
! norm2 := sqrt ( (w.*X)**C * (w.*X))
!
! Arguments:
! x - type(psb_s_vect_type) The input vector containing the entries of X.
! w - type(psb_s_vect_type) The input vector containing the entries of W.
! desc_a - type(psb_desc_type). The communication descriptor.
! info - integer. Return code
! global - logical(optional) Whether to perform the global reduction, default: .true.
!
function psb_snrm2_weight_vect(x,w, desc_a, info,global,aux) result(res)
use psb_desc_mod
use psb_check_mod
use psb_error_mod
use psb_penv_mod
use psb_s_vect_mod
implicit none
real(psb_spk_) :: res
type(psb_s_vect_type), intent (inout) :: x
type(psb_s_vect_type), intent (inout) :: w
type(psb_desc_type), intent(in) :: desc_a
integer(psb_ipk_), intent(out) :: info
logical, intent(in), optional :: global
type(psb_s_vect_type), intent(inout), optional :: aux
! locals
type(psb_ctxt_type) :: ctxt
integer(psb_ipk_) :: np, me,&
& err_act, iix, jjx, ndim, i, id, idx, ndm, ldx
integer(psb_lpk_) :: ix, jx, iy, ijy, m
logical :: global_
real(psb_spk_) :: snrm2, dd
character(len=20) :: name, ch_err
name='psb_snrm2v_weight'
call psb_erractionsave(err_act)
if (psb_errstatus_fatal()) then
info = psb_err_internal_error_ ; goto 9999
end if
info=psb_success_
ctxt=desc_a%get_context()
call psb_info(ctxt, me, np)
if (np == -1) then
info=psb_err_context_error_
call psb_errpush(info,name)
goto 9999
endif
if (.not.allocated(x%v)) then
info = psb_err_invalid_vect_state_
call psb_errpush(info,name)
goto 9999
endif
if (present(global)) then
global_ = global
else
global_ = .true.
end if
ix = 1
jx = 1
m = desc_a%get_global_rows()
ldx = x%get_nrows()
call psb_chkvect(m,lone,ldx,ix,jx,desc_a,info,iix,jjx)
if(info /= psb_success_) then
info=psb_err_from_subroutine_
ch_err='psb_chkvect'
call psb_errpush(info,name,a_err=ch_err)
end if
if (iix /= 1) then
info=psb_err_ix_n1_iy_n1_unsupported_
call psb_errpush(info,name)
goto 9999
end if
if (desc_a%get_local_rows() > 0) then
ndim = desc_a%get_local_rows()
res = x%nrm2(ndim,w,aux)
! adjust because overlapped elements are computed more than once
if (size(desc_a%ovrlap_elem,1)>0) then
if (x%is_dev()) call x%sync()
do i=1,size(desc_a%ovrlap_elem,1)
idx = desc_a%ovrlap_elem(i,1)
ndm = desc_a%ovrlap_elem(i,2)
dd = dble(ndm-1)/dble(ndm)
res = res * sqrt(sone - dd*(abs(x%v%v(idx))/res)**2)
end do
end if
else
res = szero
end if
if (global_) call psb_nrm2(ctxt,res)
call psb_erractionrestore(err_act)
return
9999 call psb_error_handler(ctxt,err_act)
return
end function psb_snrm2_weight_vect
! Function: psb_snrm2_weight_vect
! Computes the weighted norm2 of a distributed vector with respect to a mask
! contained in the vector id.
!
! norm2 := sqrt ( (w(id > 0).*X(id > 0))**C * (w(id > 0).*X(id > 0)))
!
! Arguments:
! x - type(psb_s_vect_type) The input vector containing the entries of X.
! w - type(psb_s_vect_type) The input vector containing the entries of W.
! id - type(psb_s_vect_type) The inpute vector containing the mask
! desc_a - type(psb_desc_type). The communication descriptor.
! info - integer. Return code
! global - logical(optional) Whether to perform the global reduction, default: .true.
!
function psb_snrm2_weightmask_vect(x,w,idv, desc_a, info,global, aux) result(res)
use psb_desc_mod
use psb_check_mod
use psb_error_mod
use psb_penv_mod
use psb_s_vect_mod
implicit none
real(psb_spk_) :: res
type(psb_s_vect_type), intent (inout) :: x
type(psb_s_vect_type), intent (inout) :: w
type(psb_s_vect_type), intent (inout) :: idv
type(psb_desc_type), intent(in) :: desc_a
integer(psb_ipk_), intent(out) :: info
logical, intent(in), optional :: global
type(psb_s_vect_type), intent(inout), optional :: aux
! locals
type(psb_ctxt_type) :: ctxt
integer(psb_ipk_) :: np, me,&
& err_act, iix, jjx, ndim, i, id, idx, ndm, ldx
integer(psb_lpk_) :: ix, jx, iy, ijy, m
logical :: global_
real(psb_spk_) :: snrm2, dd
character(len=20) :: name, ch_err
name='psb_snrm2v_weightmask'
call psb_erractionsave(err_act)
if (psb_errstatus_fatal()) then
info = psb_err_internal_error_ ; goto 9999
end if
info=psb_success_
ctxt=desc_a%get_context()
call psb_info(ctxt, me, np)
if (np == -1) then
info=psb_err_context_error_
call psb_errpush(info,name)
goto 9999
endif
if (.not.allocated(x%v)) then
info = psb_err_invalid_vect_state_
call psb_errpush(info,name)
goto 9999
endif
if (present(global)) then
global_ = global
else
global_ = .true.
end if
ix = 1
jx = 1
m = desc_a%get_global_rows()
ldx = x%get_nrows()
call psb_chkvect(m,lone,ldx,ix,jx,desc_a,info,iix,jjx)
if(info /= psb_success_) then
info=psb_err_from_subroutine_
ch_err='psb_chkvect'
call psb_errpush(info,name,a_err=ch_err)
end if
if (iix /= 1) then
info=psb_err_ix_n1_iy_n1_unsupported_
call psb_errpush(info,name)
goto 9999
end if
if (desc_a%get_local_rows() > 0) then
ndim = desc_a%get_local_rows()
res = x%nrm2(ndim,w,idv,info,aux)
! adjust because overlapped elements are computed more than once
if (size(desc_a%ovrlap_elem,1)>0) then
if (x%is_dev()) call x%sync()
do i=1,size(desc_a%ovrlap_elem,1)
idx = desc_a%ovrlap_elem(i,1)
ndm = desc_a%ovrlap_elem(i,2)
dd = dble(ndm-1)/dble(ndm)
res = res * sqrt(sone - dd*(abs(x%v%v(idx))/res)**2)
end do
end if
else
res = szero
end if
if (global_) call psb_nrm2(ctxt,res)
call psb_erractionrestore(err_act)
return
9999 call psb_error_handler(ctxt,err_act)
return
end function psb_snrm2_weightmask_vect
!!$
!!$ Parallel Sparse BLAS version 3.5
!!$ (C) Copyright 2006-2018
!!$ Salvatore Filippone University of Rome Tor Vergata
!!$ Alfredo Buttari
!!$
!!$ Redistribution and use in source and binary forms, with or without
!!$ modification, are permitted provided that the following conditions
!!$ are met:
!!$ 1. Redistributions of source code must retain the above copyright
!!$ notice, this list of conditions and the following disclaimer.
!!$ 2. Redistributions in binary form must reproduce the above copyright
!!$ notice, this list of conditions, and the following disclaimer in the
!!$ documentation and/or other materials provided with the distribution.
!!$ 3. The name of the PSBLAS group or the names of its contributors may
!!$ not be used to endorse or promote products derived from this
!!$ software without specific written permission.
!!$
!!$ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
!!$ ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
!!$ TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
!!$ PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PSBLAS GROUP OR ITS CONTRIBUTORS
!!$ BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
!!$ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
!!$ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
!!$ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
!!$ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
!!$ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
!!$ POSSIBILITY OF SUCH DAMAGE.
!!$
!!$
!
! Subroutine: psb_snrm2vs
! Computes the norm2 of a distributed vector, subroutine version
!
! norm2 := sqrt ( X**C * X)
!
! Arguments:
! res - real The result.
! x(:) - real The input vector containing the entries of X.
! desc_a - type(psb_desc_type). The communication descriptor.
! info - integer. Return code
! global - logical(optional) Whether to perform the global reduction, default: .true.
!
subroutine psb_snrm2vs(res, x, desc_a, info,global)
use psb_desc_mod
use psb_check_mod
use psb_error_mod
use psb_penv_mod
implicit none
real(psb_spk_), intent(in) :: x(:)
real(psb_spk_), intent(out) :: res
type(psb_desc_type), intent(in) :: desc_a
integer(psb_ipk_), intent(out) :: info
logical, intent(in), optional :: global
! locals
type(psb_ctxt_type) :: ctxt
integer(psb_ipk_) :: np, me,&
& err_act, iix, jjx, ndim, i, id, idx, ndm, ldx
integer(psb_lpk_) :: ix, jx, iy, ijy, m
logical :: global_
real(psb_spk_) :: nrm2, snrm2, dd
character(len=20) :: name, ch_err
name='psb_snrm2'
info=psb_success_
call psb_erractionsave(err_act)
if (psb_errstatus_fatal()) then
info = psb_err_internal_error_ ; goto 9999
end if
ctxt=desc_a%get_context()
call psb_info(ctxt, me, np)
if (np == -1) then
info=psb_err_context_error_
call psb_errpush(info,name)
goto 9999
endif
if (present(global)) then
global_ = global
else
global_ = .true.
end if
ix = 1
jx = 1
m = desc_a%get_global_rows()
ldx = size(x,1)
call psb_chkvect(m,lone,ldx,ix,jx,desc_a,info,iix,jjx)
if(info /= psb_success_) then
info=psb_err_from_subroutine_
ch_err='psb_chkvect'
call psb_errpush(info,name,a_err=ch_err)
end if
if (iix /= 1) then
info=psb_err_ix_n1_iy_n1_unsupported_
call psb_errpush(info,name)
goto 9999
end if
if (desc_a%get_local_rows() > 0) then
ndim = desc_a%get_local_rows()
res = snrm2( int(ndim,kind=psb_mpk_), x, int(ione,kind=psb_mpk_) )
! adjust because overlapped elements are computed more than once
do i=1,size(desc_a%ovrlap_elem,1)
idx = desc_a%ovrlap_elem(i,1)
ndm = desc_a%ovrlap_elem(i,2)
dd = real(ndm-1)/real(ndm)
res = res * sqrt(sone - dd*(abs(x(idx))/res)**2)
end do
else
res = szero
end if
if (global_) call psb_nrm2(ctxt,res)
call psb_erractionrestore(err_act)
return
9999 call psb_error_handler(ctxt,err_act)
return
end subroutine psb_snrm2vs
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