t1: RMSD REFERENCE=c_1.dat TYPE=OPTIMAL SQUARED
t2: RMSD REFERENCE=c_2.dat TYPE=OPTIMAL SQUARED 
t3: RMSD REFERENCE=c_3.dat TYPE=OPTIMAL SQUARED
t4: RMSD REFERENCE=c_4.dat TYPE=OPTIMAL SQUARED
t5: RMSD REFERENCE=c_5.dat TYPE=OPTIMAL SQUARED
MATHEVAL ...
 LABEL=dwn 
 ARG=t1,t2,t3,t4,t5
 VAR=d1,d2,d3,d4,d5
 FUNC=(exp(-770*d1)+exp(-770*d2)+exp(-770*d3)+exp(-770*d4)+exp(-770*d5))        
 PERIODIC=NO
... MATHEVAL
MATHEVAL ...
 LABEL=up 
 ARG=t1,t2,t3,t4,t5
 VAR=d1,d2,d3,d4,d5
 FUNC=(exp(-770*d1)+2*exp(-770*d2)+3*exp(-770*d3)+4*exp(-770*d4)+5*exp(-770*d5))        
 PERIODIC=NO
... MATHEVAL
MATHEVAL ...
 LABEL=s 
 ARG=up,dwn
 VAR=u,d
 FUNC=u/d        
 PERIODIC=NO
... MATHEVAL
MATHEVAL ...
 LABEL=z 
 ARG=dwn
 VAR=d
 FUNC=-(1./770.)*log(d)        
 PERIODIC=NO
... MATHEVAL
PRINT ARG=s,z STRIDE=100 FILE=colvar FMT=%8.4f
m1: METAD HEIGHT=1.2 SIGMA=0.02 PACE=60 ARG=s,z ADAPTIVE=GEOM BIASFACTOR=5 TEMP=300 
