From e210f07dd1b154275ba6ba74fa76a4fab64b3ea3 Mon Sep 17 00:00:00 2001
From: giannozz <giannozz@c92efa57-630b-4861-b058-cf58834340f0>
Date: Fri, 4 Apr 2008 13:58:13 +0000
Subject: [PATCH] There was a nasty bug in the real-space approach to Q(r) of
 USPP: if the physical and true dimensions of the charge density array were
 different, the algorithm was filling non physical locations of the array as
 well

git-svn-id: http://qeforge.qe-forge.org/svn/q-e/trunk/espresso@4772 c92efa57-630b-4861-b058-cf58834340f0
---
 PW/realus.f90 | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/PW/realus.f90 b/PW/realus.f90
index 51f882226..02d59454e 100644
--- a/PW/realus.f90
+++ b/PW/realus.f90
@@ -155,14 +155,10 @@ MODULE realus
       !
       ! ... now we find the points
       !
-      idx0 = 0
-      !
 #if defined (__PARA)
-      !
-      DO i = 1, me_pool
-         idx0 = idx0 + nrx1*nrx2*dfftp%npp(i)
-      END DO
-      !
+      idx0 = nrx1*nrx2 * SUM ( dfftp%npp(1:me_pool) )
+#else
+      idx0 = 0
 #endif
       !
       inv_nr1 = 1.D0 / DBLE( nr1 )
@@ -183,7 +179,7 @@ MODULE realus
          !
          DO ir = 1, nrxx
             !
-            ! ... three dimensional indexes
+            ! ... three dimensional indices (i,j,k)
             !
             idx   = idx0 + ir - 1
             k     = idx / (nrx1*nrx2)
@@ -192,6 +188,10 @@ MODULE realus
             idx   = idx - nrx1*j
             i     = idx
             !
+            ! ... do not include points outside the physical range!
+            !
+            IF ( i >= nr1 .or. j >= nr2 .or. k >= nr3 ) CYCLE
+            !
             DO ipol = 1, 3
                posi(ipol) = DBLE( i )*inv_nr1*at(ipol,1) + &
                             DBLE( j )*inv_nr2*at(ipol,2) + &