I tried to use yt to analyse Illustris-1 data. However, yt can not load the data. When I use the command ds = yt.load("/scratch/Illustris/Illustris-1/snapdir_135/snap_135.0.hdf5") I get this response yt : [INFO ] 2018-06-24 18:03:58,721 Calculating time from 1.000e+00 to be 4.340e+17 seconds yt : [INFO ] 2018-06-24 18:03:58,721 Assuming length units are in kpc/h (comoving) yt : [INFO ] 2018-06-24 18:03:58,803 Parameters: current_time = 4.3395518355981376e+17 s yt : [INFO ] 2018-06-24 18:03:58,803 Parameters: domain_dimensions = [2 2 2] yt : [INFO ] 2018-06-24 18:03:58,804 Parameters: domain_left_edge = [0. 0. 0.] yt : [INFO ] 2018-06-24 18:03:58,804 Parameters: domain_right_edge = [75000. 75000. 75000.] yt : [INFO ] 2018-06-24 18:03:58,804 Parameters: cosmological_simulation = 1 yt : [INFO ] 2018-06-24 18:03:58,804 Parameters: current_redshift = 2.220446049250313e-16 yt : [INFO ] 2018-06-24 18:03:58,804 Parameters: omega_lambda = 0.7274 yt : [INFO ] 2018-06-24 18:03:58,804 Parameters: omega_matter = 0.2726 yt : [INFO ] 2018-06-24 18:03:58,804 Parameters: hubble_constant = 0.704 yt : [INFO ] 2018-06-24 18:03:59,093 Allocating for 1.793e+10 particles (index particle type 'all') yt : [INFO ] 2018-06-24 19:53:51,036 Identified 7.700e+08 octs /var/spool/pbs/mom_priv/jobs/306683.venus.SC: line 8: 185742 Segmentation fault (core dumped) What's wrong with yt?