subroutine tenrgy(tm,wdtt,wtt)
c
c  Volume integral of (del (tm)/d(theta))**2
c
      implicit none
      include 'itg.par'
c
      real tm(lz,mz,nz,nspecz),wtt(mz,nz),coef,wdtt,qmr,qnr,delt
      integer mr,l,m,n
      include 'itg.cmn'
c
c ... note that dr(l)=2.0*dx
c     ... normalize by delta=pi*y0 in the x-direction
c
      coef=0.25/(pi*y0)
      wdtt=0.0
c
      do 10 n=1,nd
      qnr=float(nrr(n))/z0
      do 10 m=1,md
      mr=mrr(m,n)
      qmr=float(mr)/y0
      wtt(m,n)=0.0
      delt=(qmr*bdel(1)-qnr)*tm(1,m,n,1)
      wtt(m,n)=wtt(m,n)+delt*delt*dr(1)*0.5
      do 20 l=2,ldb
      delt=(qmr*bdel(l)-qnr)*tm(l,m,n,1)
      wtt(m,n)=wtt(m,n)+delt*delt*dr(l)
   20 continue
      delt=(qmr*bdel(ld)-qnr)*tm(ld,m,n,1)
      wtt(m,n)=wtt(m,n)+delt*delt*dr(ld)*0.5
      wtt(m,n)=coef*wtt(m,n)
      wdtt=wdtt+wtt(m,n)
   10 continue
c
      return
      end