Some more smallbox cleanup

git-svn-id: http://qeforge.qe-forge.org/svn/q-e/trunk/espresso@7472 c92efa57-630b-4861-b058-cf58834340f0

CPV/cplib.f90

@@ -90,7 +90,6 @@
           USE gvecw, ONLY: ecutwfc,  gcutw
           USE gvect, ONLY: ecutrho,  gcutm
           USE gvecs, ONLY: ecuts, gcutms
-          USE smallbox_gvec, ONLY: ecutb, gcutb
           USE gvecw, ONLY: ekcut, gkcut
           USE constants, ONLY: eps8, pi
 
@@ -153,7 +152,6 @@
         USE gvecw, ONLY: ecfixed, qcutz, q2sigma
         USE gvecw, ONLY: ekcut, gkcut
         USE gvecs, ONLY: ecuts, gcutms
-        USE smallbox_gvec, ONLY: ecutb, gcutb
         use betax, only: mmx, refg
         USE io_global, ONLY: stdout
 

CPV/init.f90

@@ -25,7 +25,7 @@
       use control_flags,        only: gamma_only, iprsta
       use grid_dimensions,      only: nr1, nr2, nr3
       use cell_base,            only: ainv, at, omega, alat
-      use small_box,            only: tpibab, bgb, small_box_set
+      use small_box,            only: small_box_set
       use smallbox_grid_dim,    only: nr1b, nr2b, nr3b, &
                                       smallbox_grid_init,smallbox_grid_info
       USE grid_subroutines,     ONLY: realspace_grids_init, realspace_grids_info
@@ -35,7 +35,6 @@
                                       ecutrho, gcutm, gvect_init
       use gvecs,                only: gcutms, gvecs_init
       use gvecw,                only: gkcut, gvecw_init, g2kin_init
-      use smallbox_gvec,        only: gcutb
       USE smallbox_subs,        ONLY: ggenb
       USE fft_base,             ONLY: dfftp, dffts
       USE fft_scalar,           ONLY: cft_b_omp_init
@@ -156,24 +155,22 @@
       allocate( eigts2(-nr2:nr2,nat) )
       allocate( eigts3(-nr3:nr3,nat) )
       !
-      !     generation of little box g-vectors
+      !     small boxes
       !
       IF ( nr1b > 0 .AND. nr2b > 0 .AND. nr3b > 0 ) THEN
 
-         !  sets the small box parameters
+         !  set the small box parameters
 
          rat1 = DBLE( nr1b ) / DBLE( nr1 )
          rat2 = DBLE( nr2b ) / DBLE( nr2 )
          rat3 = DBLE( nr3b ) / DBLE( nr3 )
-         CALL small_box_set( alat, omega, at, rat1, rat2, rat3 )
-
-         !  now set gcutb
-
-         gcutb = ecutrho / tpibab / tpibab
          !
-         CALL ggenb ( bgb, gcutb, iprsta )
+         CALL small_box_set( alat, omega, at, rat1, rat2, rat3 )
-
+         !
-         ! initialize FFT table
+         !  generate small-box G-vectors, initialize FFT tables
+         !
+         CALL ggenb ( ecutrho, iprsta )
+         !
 #if defined __OPENMP && defined __FFTW 
          CALL cft_b_omp_init( nr1b, nr2b, nr3b )
 #endif
@@ -338,7 +335,7 @@
       USE gvecw,                 ONLY : g2kin_init
       USE gvect,                 ONLY : g, gg, ngm, mill
       USE grid_dimensions,       ONLY : nr1, nr2, nr3
-      USE small_box,             ONLY : bgb, small_box_set
+      USE small_box,             ONLY : small_box_set
       USE smallbox_subs,         ONLY : gcalb
       USE io_global,             ONLY : stdout, ionode
       USE smallbox_grid_dim,     ONLY : nr1b, nr2b, nr3b
@@ -380,7 +377,7 @@
       rat3 = DBLE( nr3b ) / DBLE( nr3 )
       CALL small_box_set( alat, omega, at, rat1, rat2, rat3 )
       !
-      call gcalb ( bgb )
+      call gcalb ( )
       !
       return
     end subroutine newinit

CPV/smallbox_gvec.f90

@@ -13,30 +13,23 @@
      IMPLICIT NONE
      SAVE
 
-     ! ...   G vectors less than the box grid cut-off ( ? )
+     ! ...   Variables describing G-vectors for the small box grid 
+     ! ...   Basically the same meaning as for the corresponding 
+     ! ...   quantities for the true lattice
+     !
      INTEGER :: ngb  = 0  ! local number of G vectors
-     INTEGER :: ngbt = 0  ! in parallel execution global number of G vectors,
-                       ! in serial execution this is equal to ngw
      INTEGER :: ngbl = 0  ! number of G-vector shells up to ngw
-     INTEGER :: ngbx = 0  ! maximum local number of G vectors
 
-     REAL(DP), ALLOCATABLE :: gb(:), gxb(:,:), glb(:)
+     REAL(DP), ALLOCATABLE :: gb(:)    ! G(i)^2 in (tpi/alatb)**2 units
-     INTEGER, ALLOCATABLE :: npb(:), nmb(:)
+     REAL(DP), ALLOCATABLE :: gxb(:,:) ! G(:,i) in  tpi/alatb     units
-     INTEGER, ALLOCATABLE :: mill_b(:,:)
+     REAL(DP), ALLOCATABLE :: glb(:)   ! shells of G(i)^2
+     INTEGER, ALLOCATABLE :: npb(:), nmb(:) ! FFT indices
+     INTEGER, ALLOCATABLE :: mill_b(:,:)    ! miller indices
 
-     REAL(DP) :: ecutb = 0.0_DP
+     REAL(DP) :: gcutb = 0.0_DP  ! effective cut-off in (tpi/alatb)**2 units
-     REAL(DP) :: gcutb = 0.0_DP
 
    CONTAINS
 
-     SUBROUTINE smallbox_gvec_set( ecut, tpibab )
-       IMPLICIT NONE
-       REAL(DP), INTENT(IN) :: ecut, tpibab
-         ecutb = ecut
-         gcutb = ecut / tpibab / tpibab
-       RETURN
-     END SUBROUTINE smallbox_gvec_set
-
      SUBROUTINE deallocate_smallbox_gvec()
        IF( ALLOCATED( gb ) ) DEALLOCATE( gb )
        IF( ALLOCATED( gxb ) ) DEALLOCATE( gxb )

CPV/smallbox_subs.f90

@@ -14,8 +14,8 @@ MODULE smallbox_subs
 !  ... G-vector components onto the FFT grid(s) in reciprocal space
 !  ... Small-Box grid
 
-   USE smallbox_gvec, ONLY :  ngb, ngbt, ngbl, ngbx, gb, gxb, glb, &
+   USE small_box, ONLY :  bgb, tpibab
-                              npb, nmb, mill_b
+   USE smallbox_gvec, ONLY :  ngb, ngbl, gb, gxb, glb, npb, nmb, mill_b, gcutb
    USE smallbox_grid_dim, ONLY : nr1b, nr2b, nr3b, nr1bx, nr2bx, nr3bx
 
    PRIVATE
@@ -27,7 +27,7 @@ MODULE smallbox_subs
 CONTAINS
 !=----------------------------------------------------------------------=
   !
-  SUBROUTINE ggenb ( bgb, gcutb, iprsta )
+  SUBROUTINE ggenb ( ecutrho, iprsta )
     !-----------------------------------------------------------------------
     !
     ! As ggen, for the box grid. A "b" is appended to box variables.
@@ -38,7 +38,7 @@ CONTAINS
     !
     IMPLICIT NONE
     !
-    REAL(DP), INTENT(in) :: bgb(3,3), gcutb
+    REAL(DP), INTENT(in) :: ecutrho
     INTEGER, INTENT (in) :: iprsta
     !
     INTEGER, ALLOCATABLE:: idx(:), iglb(:)
@@ -46,6 +46,10 @@ CONTAINS
     INTEGER it, icurr, nr1m1, nr2m1, nr3m1, ir, ig, i,j,k, itv(3), ip
     REAL(DP) t(3), g2
     !
+    !   gcutb is the effective cut-off for G-vectors of the small box grid
+    !
+    gcutb = ecutrho / tpibab**2
+    !    
     nr1m1=nr1b-1
     nr2m1=nr2b-1
     nr3m1=nr3b-1
@@ -261,7 +265,7 @@ CONTAINS
   END SUBROUTINE gshcount
   !
   !
-  SUBROUTINE gcalb ( bgb )
+  SUBROUTINE gcalb ( )
     !
     !     re-generation of little box g-vectors
     !
@@ -269,7 +273,6 @@ CONTAINS
     !
     IMPLICIT NONE
     !
-    REAL(DP), INTENT(in) :: bgb(3,3)
     INTEGER :: ig, i1,i2,i3
 
     IF ( nr1b == 0 .OR. nr2b == 0 .OR. nr3b == 0 ) return