SUBROUTINE  saxpy(  a,  scala, b,  scalb  )
      USE numerics
      IMPLICIT  NONE
      INCLUDE 'comthd.h'
      REAL(rp),  DIMENSION(sx-1:ex+1,sy-1:ey+1,sz-1:ez+1),  INTENT(INOUT)  ::  a
      REAL(rp),  DIMENSION(sx-1:ex+1,sy-1:ey+1,sz-1:ez+1),  INTENT(IN)     ::  b
      REAL(rp),  INTENT(IN)  ::  scala
      REAL(rp),  INTENT(IN)  ::  scalb
      END SUBROUTINE saxpy