[IMP-dev] rmf file size

[Riccardo Pellarin <>]

Hi all. I'm using the rmf file support to write coordinates of my
optimization run.
I set up the rmf file in this way

rh = RMF.create_rmf_file("traj.rmf")
IMP.rmf.add_hierarchy(rh, self.prot)

and then at each step "i" I save the coordinates in the file

for i in range(10000):
    mc.optimize(100)
    IMP.rmf.save_frame(rh,i)

Now, the resulting rmf file for my system has a size of about 100 KB per frame,
which is only slightly lower than the 120 KB per frame of an appended pdb
file. (My optimization run saves 100000 frames, which makes about 10 GB
for the rmf). How is it possible that a binary file is that bulky?
For comparison, a dcd trajectory frame only occupies 18 KB,  for the
same system.

Am I doing something wrong?

cheers

Riccardo