Out-of-core calculations with md.iterload()

An error occurred while executing the following cell: ------------------ first_frame = md.load_frame(traj_filename, 0) first_frame ------------------ --------------------------------------------------------------------------- OSError Traceback (most recent call last) Cell In[3], line 1 ----> 1 first_frame = md.load_frame(traj_filename, 0)  2 first_frame File ~/checkouts/readthedocs.org/user_builds/mdtraj/envs/latest/lib/python3.13/site-packages/mdtraj/core/trajectory.py:338, in load_frame(filename, index, top, atom_indices, **kwargs)  336 if not _is_url(filename):  337 if loader.__name__ not in ["load_dtr"]: --> 338 _assert_files_exist(filename)  339 else:  340 _assert_files_or_dirs_exist(filename) File ~/checkouts/readthedocs.org/user_builds/mdtraj/envs/latest/lib/python3.13/site-packages/mdtraj/core/trajectory.py:116, in _assert_files_exist(filenames)  114 for fn in filenames:  115 if not (os.path.exists(fn) and os.path.isfile(fn)): --> 116 raise OSError("No such file: %s" % fn) OSError: No such file: data/frame0.h5

(iterload.ipynb; iterload_eval.ipynb; iterload.py)