get_acc Subroutine

    pure subroutine get_acc(self, particles)
        class(float_object_type), intent(inout) :: self  !! 浮体粒子集
        type(particle_type), intent(in) :: particles  !! 区域
        real(rk) :: force(2), torque
        integer :: i

        force = 0.0_rk
        torque = 0.0_rk
        do i = self%istart, self%iend
            force = force + particles%acc(:, i)*particles%mass(i)
            torque = torque + cross_product_local(particles%loc(:, i) - self%loc(:), &
                                                  particles%acc(:, i)*particles%mass(i))
        end do
        self%acc = force/self%mass(1)
        self%ang_acc = torque/self%mass(2)

    end subroutine get_acc