Fixed sign error in posres dvdl

[alexxy/gromacs.git] / src / gmxlib / bondfree.c

diff --git a/src/gmxlib/bondfree.c b/src/gmxlib/bondfree.c
index 2c25351ec20380e4eb27ad9e2c535f451ba0c5f4..e9f68b3c10337e2ed807f86df9d5a906fcf09f37 100644 (file)
--- a/src/gmxlib/bondfree.c
+++ b/src/gmxlib/bondfree.c
@@ -2297,7 +2297,7 @@ real posres(int nbonds,
             vtot       += 0.5*kk*dx[m]*dx[m];
             *dvdlambda +=
                 0.5*(pr->posres.fcB[m] - pr->posres.fcA[m])*dx[m]*dx[m]
-                -fm*dpdl[m];
+                + fm*dpdl[m];
 
             /* Here we correct for the pbc_dx which included rdist */
             if (bForceValid)