Merge release-4-6 into master

[alexxy/gromacs.git] / src / gromacs / mdlib / force.c

diff --git a/src/gromacs/mdlib/force.c b/src/gromacs/mdlib/force.c
index c2301f8414a7fd64c99b64b3ab1be96c5041a75e..40a1c5d22e81a9ae67cdf1bfd20edb2b2ac0deea 100644 (file)
--- a/src/gromacs/mdlib/force.c
+++ b/src/gromacs/mdlib/force.c
@@ -803,6 +803,9 @@ void sum_dhdl(gmx_enerdata_t *enerd, real *lambda, t_lambda *fepvals)
             /* could this be done more readably/compactly? */
             switch (i)
             {
+                case (efptMASS):
+                    index = F_DKDL;
+                    break;
                 case (efptCOUL):
                     index = F_DVDL_COUL;
                     break;
@@ -815,9 +818,6 @@ void sum_dhdl(gmx_enerdata_t *enerd, real *lambda, t_lambda *fepvals)
                 case (efptRESTRAINT):
                     index = F_DVDL_RESTRAINT;
                     break;
-                case (efptMASS):
-                    index = F_DKDL;
-                    break;
                 default:
                     index = F_DVDL;
                     break;
@@ -858,21 +858,13 @@ void sum_dhdl(gmx_enerdata_t *enerd, real *lambda, t_lambda *fepvals)
                                                  so we don't need to add anything to the
                                                  enerd->enerpart_lambda[0] */
 
-        /* we don't need to worry about dvdl contributions to the current lambda, because
-           it's automatically zero */
-
-        /* first kinetic energy term */
-        dlam = (fepvals->all_lambda[efptMASS][i] - lambda[efptMASS]);
-
-        enerd->enerpart_lambda[i+1] += enerd->term[F_DKDL]*dlam;
+        /* we don't need to worry about dvdl_lin contributions to dE at
+           current lambda, because the contributions to the current
+           lambda are automatically zeroed */
 
         for (j = 0; j < efptNR; j++)
         {
-            if (j == efptMASS)
-            {
-                continue;
-            }                            /* no other mass term to worry about */
-
+            /* Note that this loop is over all dhdl components, not just the separated ones */
             dlam = (fepvals->all_lambda[j][i]-lambda[j]);
             enerd->enerpart_lambda[i+1] += dlam*enerd->dvdl_lin[j];
             if (debug)