Missing variables initialization.

In some cases this can cause issues if the compiler does not set to 0
but to random values.

EPW/src/dynmat_asr.f90

@@ -50,7 +50,7 @@
   !! Set of symmetry operations
   INTEGER, INTENT(in) :: irt(48, nat)
   !! For each atoms give the rotated atoms
-  REAL(KIND = DP), INTENT(inout) :: sxq(3, 48)
+  REAL(KIND = DP), INTENT(in) :: sxq(3, 48)
   !! Symmetry matrix
   REAL(KIND = DP), INTENT(inout) :: rtau(3, 48, nat)
   !! the relative position of the rotated atom to the original one
@@ -132,8 +132,6 @@
   !!
   INTEGER :: nqs
   !!
-  INTEGER :: axis
-  !!
   INTEGER :: nrws
   !!
   INTEGER :: ierr
@@ -205,8 +203,8 @@
   COMPLEX(KIND = DP), ALLOCATABLE :: dyn(:, :, :, :) ! 3,3,nat,nat
   !! Dynamical matrix
   !
-  axis = 3
-  !
+  q(:, :) = zero
+  ! 
   ! the call to set_ndnmbr is just a trick to get quickly
   ! a file label by exploiting an existing subroutine
   ! (if you look at the sub you will find that the original

EPW/src/elphon_shuffle_wrap.f90

@@ -415,6 +415,7 @@
     bmat(:, :, :, :)      = czero
     cu(:, :, :)           = czero
     cuq(:, :, :)          = czero
+    sxq(:, :)             = zero
     !
     ! read interatomic force constat matrix from q2r
     IF (lifc) THEN
@@ -496,7 +497,7 @@
          INQUIRE(FILE = TRIM(filename), EXIST = exst)
          IF (.NOT. exst) CALL errore('elphon_shuffle_wrap', &
                    'cannot open file for reading or writing', ierr)
-         CALL read_disp_pattern_only (iunpattern, filename, iq_irr, ierr)
+         CALL read_disp_pattern_only(iunpattern, filename, iq_irr, ierr)
          IF (ierr /= 0) CALL errore('elphon_shuffle_wrap', ' Problem with modes file', 1)
       ENDIF
       !
@@ -533,7 +534,7 @@
       ! ######################### star of q #########################
       !
       sym_smallq(:) = 0
-      CALL star_q2(xq, at, bg, nsym, s, invs, nq, sxq, isq, imq, .TRUE., sym_smallq)
+      CALL star_q2(xq, at, bg, nsym, s, invs, t_rev, nq, sxq, isq, imq, .TRUE., sym_smallq)
       IF (fixsym) THEN
         IF (epw_noinv) imq = 1 ! Any non-zero integer is ok.
       ENDIF
@@ -719,7 +720,7 @@
         ! are equal to 5+ digits).
         ! For any volunteers, please write to giustino@civet.berkeley.edu
         !
-        CALL elphon_shuffle(iq_irr, nqc_irr, nqc, gmapsym(:,isym1), eigv(:,isym1), isym, xq0, .FALSE.)
+        CALL elphon_shuffle(iq_irr, nqc_irr, nqc, gmapsym(:, isym1), eigv(:, isym1), isym, xq0, .FALSE.)
         !
         !  bring epmatq in the mode representation of iq_first,
         !  and then in the cartesian representation of iq
@@ -763,7 +764,7 @@
           !
           xq0 = -xq0
           !
-          CALL elphon_shuffle(iq_irr, nqc_irr, nqc, gmapsym(:,isym1), eigv(:,isym1), isym, xq0, .TRUE.)
+          CALL elphon_shuffle(iq_irr, nqc_irr, nqc, gmapsym(:, isym1), eigv(:, isym1), isym, xq0, .TRUE.)
           !  bring epmatq in the mode representation of iq_first,
           !  and then in the cartesian representation of iq
           !

EPW/src/rotate.f90

@@ -436,7 +436,7 @@
     !---------------------------------------------------------------------------
     !
     !-----------------------------------------------------------------------
-    SUBROUTINE star_q2(xq, at, bg, nsym, s, invs, nq, sxq, isq, imq, verbosity, sym_smallq)
+    SUBROUTINE star_q2(xq, at, bg, nsym, s, invs, t_rev, nq, sxq, isq, imq, verbosity, sym_smallq)
     !-----------------------------------------------------------------------
     !!
     !! Generate the star of q vectors that are equivalent to the input one
@@ -457,6 +457,8 @@
     !! Symmetry operations
     INTEGER, INTENT(in) :: invs(48)
     !! list of inverse operation indices
+    INTEGER, INTENT(in) :: t_rev(48)
+    !! Time-reveral sym
     INTEGER, INTENT(out) :: nq
     !! degeneracy of the star of q
     INTEGER, INTENT(out) :: isq(48)
@@ -469,7 +471,7 @@
     !! direct lattice vectors
     REAL(KIND = DP), INTENT(in) :: bg(3, 3)
     !! reciprocal lattice vectors
-    REAL(KIND = DP), INTENT(out) :: sxq(3, 48)
+    REAL(KIND = DP), INTENT(inout) :: sxq(3, 48)
     !! list of vectors in the star of q
     !
     ! Local variables
@@ -499,6 +501,7 @@
     !! Tolerence
     !
     zero(:) = 0.d0
+    saq(:, :) = 0.0d0
     !
     ! go to  crystal coordinates
     !
@@ -525,6 +528,8 @@
                    + bg(i, 2) * raq(2) &
                    + bg(i, 3) * raq(3)
       ENDDO
+      IF (t_rev(isym) == 1) raq = -raq
+      !  
       DO iq = 1, nq
         IF (eqvect(raq, saq(1, iq), zero, accep)) THEN
           isq(isym) = iq

LR_Modules/star_q.f90

@@ -57,6 +57,7 @@ subroutine star_q1(xq, at, bg, nsym, s, invs, nq, sxq, isq, imq, verbosity,&
   !
   !
   zero(:) = 0.d0
+  saq(:, :) = 0.0d0 
   !
   ! go to  crystal coordinates
   !
@@ -176,6 +177,7 @@ subroutine star_q (xq, at, bg, nsym, s, invs, nq, sxq, isq, imq, verbosity)
   !
   !
   zero(:) = 0.d0
+  saq(:, :) = 0.0d0 
   !
   ! go to  crystal coordinates
   !