dear rick,

as I would like to focus on the distribution of that angle,

let say, I would like to get the histogram from 0-180 degree on the x-axis and probability on the y-axis.

and I did it via following script (based on your script), is it correct?

enter aav zero

edit aav total 180 delta 1. offset 0 skip 1

enter bav dupl aav

! LOOP OVER LIPIDS; DEFINE VECTOR LENGTH (R) AND Z COMPONENT

set k 1

label elp

enter

r@K vect r L @K C23 L @K C213 ! BETA CHAIN

enter

s@K vect r L @K C33 L @K C313 ! GAMMA CHAIN

enter

z@K vect z L @K C23 L @K C213

enter

w@K vect z L @K C33 L @K C313

incr k by 1

if k le 224 goto elp

! OPEN FILES (COPIED TO /scratch FOR EFFICIENCY)

open unit 8 file name lipid.dcd

traj first 8 nunit 1 skip 2500

set k 1

label tlp

! NORMALIZE Z COMPONENT (DIVIDE BY R)

mantim

z@K ratio

r@Kmantim

w@K ratio

s@K! IGNORE SIGN; NEEDED TO AVG OVER BOTH LEAFLETS

mantim

z@K acos

mantim

w@K acos

mantim

z@K hist 0 180 180

mantim

w@K hist 0 180 180

mantime aav add

z@Kmantime bav add

w@Kincr k by 1

if k le 224 goto tlp

mantim aav divi 224.

mantim bav divi 224.

!mantim aav acos

!mantim bav acos

! OUTPUT FILE WITH (TIME, BETA-TILT, GAMMA-TILT) FOR EACH TIME POINT

edit aav total 180 delta 1 offset 0 skip 1 veccod 2

open unit 2 write card name cahin_distribu.dat

write aav unit 2 dumb time

* dummy

*