submodule(forlab_linalg) forlab_linalg_norm
implicit none
contains
real(sp) module function norm1_sp(x, p)
real(sp), dimension(:), intent(in) :: x
real(sp), intent(in), optional :: p
real(sp)::temp
if (.not. present(p)) then
temp = 2.0_sp
else
temp = p
end if
if (temp == 2.0_sp) then
norm1_sp = sqrt(sum(abs(x)**2))
elseif (temp == 1.0_sp) then
norm1_sp = sum(abs(x))
else
norm1_sp = (sum(abs(x)**p))**(1.0_sp/p)
end if
end function norm1_sp
real(sp) module function norm2_sp(A, p)
real(sp), dimension(:, :), intent(in) :: A
real(sp), intent(in), optional :: p
real(sp)::temp
real(sp), dimension(:), allocatable :: w
if (.not. present(p)) then
temp = 2.0_sp
else
temp = p
end if
if (temp == 2.0_sp) then
call svd(A, w)
norm2_sp = maxval(w)
elseif (temp == 1.0_sp) then
norm2_sp = maxval(sum(abs(A), dim=2))
end if
end function norm2_sp
real(dp) module function norm1_dp(x, p)
real(dp), dimension(:), intent(in) :: x
real(dp), intent(in), optional :: p
real(dp)::temp
if (.not. present(p)) then
temp = 2.0_dp
else
temp = p
end if
if (temp == 2.0_dp) then
norm1_dp = sqrt(sum(abs(x)**2))
elseif (temp == 1.0_dp) then
norm1_dp = sum(abs(x))
else
norm1_dp = (sum(abs(x)**p))**(1.0_dp/p)
end if
end function norm1_dp
real(dp) module function norm2_dp(A, p)
real(dp), dimension(:, :), intent(in) :: A
real(dp), intent(in), optional :: p
real(dp)::temp
real(dp), dimension(:), allocatable :: w
if (.not. present(p)) then
temp = 2.0_dp
else
temp = p
end if
if (temp == 2.0_dp) then
call svd(A, w)
norm2_dp = maxval(w)
elseif (temp == 1.0_dp) then
norm2_dp = maxval(sum(abs(A), dim=2))
end if
end function norm2_dp
end submodule forlab_linalg_norm
