c
c     Points (z) and weights (w) on velocity, pressure
c
c     zgl -- velocity points on Gauss-Lobatto points i = 1,...nx
c     zgp -- pressure points on Gauss         points i = 1,...nxp (nxp = nx-2)
c

c     integer    lxm ! defined in HSMG
c     parameter (lxm = lx1)
      integer    lxq
      parameter (lxq = lx2)
c
      real         zgl(lx1), wgl(lx1), zgp(lx1), wgp(lxq)
      common /wz1/ zgl     , wgl     , zgp     , wgp
c
c     Tensor- (outer-) product of 1D weights   (for volumetric integration)
c
      real         wgl1(lx1*lx1), wgl2(lxq*lxq), wgli(lx1*lx1)
      common /wz2/ wgl1         , wgl2         , wgli
c
c
c    Frequently used derivative matrices:
c
c    D1, D1t   ---  differentiate on mesh 1 (velocity mesh)
c    D2, D2t   ---  differentiate on mesh 2 (pressure mesh)
c
c    DXd,DXdt  ---  differentiate from velocity mesh ONTO dealiased mesh
c                   (currently the same as D1 and D1t...)
c
c
      real d1    (lx1*lx1) , d1t    (lx1*lx1)
     $   , d2    (lx1*lx1) , b2p    (lx1*lx1)
     $   , B1iA1 (lx1*lx1) , B1iA1t (lx1*lx1)
     $   , da    (lx1*lx1) , dat    (lx1*lx1)
     $   , iggl  (lx1*lxq) , igglt  (lx1*lxq)
     $   , dglg  (lx1*lxq) , dglgt  (lx1*lxq)
     $   , wglg  (lx1*lxq) , wglgt  (lx1*lxq)
      common /deriv/  d1,d1t,d2,b2p,B1iA1,B1iA1t
     $    ,da,dat,iggl,igglt,dglg,dglgt,wglg,wglgt
