INCLUDE FILE=aa
UNITS TIME=0.1 LENGTH=0.1 ENERGY=10
g1: GROUP ATOMS=1-10
g2: ...
  GROUP ATOMS={30-40
5}
...
c1: CENTER   ATOMS={g1}
c2: CENTER   ATOMS=g2 NOPBC

INCLUDE FILE=dd

RESTRAINT ARG=d2 AT=9 KAPPA=0.003

PRINT ...
  STRIDE=1
  ARG={
     d1 d2 d3
  }
  FILE=COLVAR FMT=%6.3f
... PRINT

ENDPLUMED

