),1)                       (2)
          has the smallest value for the scaled submatrices.
          If THRESH = -4, the norm reduction in (2) is tried, but
          the subroutine may return IWARN = 1 and reset the scaling
          factors to 1, as for THRESH = -2 above.
          If THRESH = -VALUE, with VALUE &gt;= 10, the condition
          numbers of the left and right scaling transformations will
          be bounded by VALUE, i.e., the ratios between the largest
          and smallest entries in 