anchor.diff:              do j = 1,p%numBladeNodes
               
                  if ( EqualRealNos(z%phi(j,k), 0.0_ReKi) ) then
  -                  call SetErrStat(ErrID_Fatal,"Blade"//trim(num2lstr(k))//', node '//trim(num2lstr(k))//&
  +                  call SetErrStat(ErrID_Fatal,"Blade"//trim(num2lstr(k))//', node '//trim(num2lstr(j))//&
                          ": residual is discontinuous or undefined because z%phi = 0.",ErrStat,ErrMsg,RoutineName)
                     return
                  else if ( VelocityIsZero(u%Vy(j,k)) ) then
  -                  call SetErrStat(ErrID_Fatal,"Blade"//trim(num2lstr(k))//', node '//trim(num2lstr(k))//&
  +                  call SetErrStat(ErrID_Fatal,"Blade"//trim(num2lstr(k))//', node '//trim(num2lstr(j))//&
                          ": residual is discontinuous or undefined because u%Vy = 0.",ErrStat,ErrMsg,RoutineName)
                     return
                  else if ( VelocityIsZero(u%Vx(j,k)) ) then
  -                  call SetErrStat(ErrID_Fatal,"Blade"//trim(num2lstr(k))//', node '//trim(num2lstr(k))//&
  +                  call SetErrStat(ErrID_Fatal,"Blade"//trim(num2lstr(k))//', node '//trim(num2lstr(j))//&
                          ": residual is discontinuous or undefined because u%Vx = 0.",ErrStat,ErrMsg,RoutineName)
                     return
                  end if
  
positive.code:             do j = 1,p%numBladeNodes
              
                 if ( VelocityIsZero( u%Vy(j,k)+m%TnInd_op(j,k)) .and. VelocityIsZero( u%Vx(j,k)+m%AxInd_op(j,k) ) ) then
                    call SetErrStat(ErrID_Fatal,"Blade"//trim(num2lstr(k))//', node '//trim(num2lstr(k))//&
                        ": residual is undefined because u%Vy + TnInd_op = u%Vx + AxInd_op = 0.",ErrStat,ErrMsg,RoutineName)
                    return
                 end if
  
negative.code:          do j = 1,p%numBladeNodes
              
              if ( EqualRealNos( u%Vy(j,k), 0.0_ReKi ) .and. EqualRealNos( u%Vx(j,k), 0.0_ReKi ) ) then
                 call SetErrStat(ErrID_Fatal,"Blade"//trim(num2lstr(k))//', node '//trim(num2lstr(j))//&
                      ": residual is undefined because u%Vy = u%Vx = 0.",ErrStat,ErrMsg,RoutineName)
                 return
              end if
  