HDF5 Wrapper
The hdf5-wrapper python package adds a wrapper to h5py that greatly simplifies reading/writing to/from hdf5-format files.
Usage
Once loaded, the contents of a file can be navigated in the same way as a native python dictionary.
from geos.hdf5_wrapper import hdf5_wrapper
data = hdf5_wrapper('data.hdf5')
test = data['test']
for k, v in data.items():
print('key: %s, value: %s' % (k, str(v)))
If the user indicates that a file should be opened in write-mode (w) or read/write-mode (a), then the file can be created or modified. Note: for these changes to be written to the disk, the wrapper may need to be closed or deleted.
from geos.hdf5_wrapper import hdf5_wrapper
import numpy as np
data = hdf5_wrapper('data.hdf5', mode='w')
data['string'] = 'string'
data['integer'] = 123
data['array'] = np.random.randn(3, 4, 5)
data['child'] = {'float': 1.234}
Existing dictionaries can be placed on the current level:
existing_dict = {'some': 'value'}
data.insert(existing_dict)
And external hdf5 format files can be linked together:
for k in ['child_a', 'child_b']:
data.link(k, '%s.hdf5' % (k))
API
- class geos.hdf5_wrapper.wrapper.hdf5_wrapper(fname='', target=None, mode='r')[source]
A class for reading/writing hdf5 files, which behaves similar to a native dict
Initialize the hdf5_wrapper class
If the fname is supplied (either by a positional or keyword argument), the wrapper will open a hdf5 database from the filesystem. The recommended options for the mode flag include ‘r’ for read-only and ‘a’ for read/write access. If write mode is enabled, and the fname does not point to an existing file, a new database will be created.
If the target is supplied, then a new instance of the wrapper will be created using an existing database handle.
- Parameters:
fname (str) – the filename of a new or existing hdf5 database
target (hdf5_wrapper) – the handle of an existing hdf5 dataset
mode (str) – the read/write behavior of the database (default=’r’)
- copy()[source]
Copy the entire database into memory
- Returns:
a dictionary holding the database contents
- Return type:
dict
- get_copy()[source]
Copy the entire database into memory
- Returns:
a dictionary holding the database contents
- Return type:
dict
- insert(x)[source]
Insert the contents of the target object to the current location
- Parameters:
x (dict, hdf5_wrapper) – the dictionary to insert
- keys()[source]
Get a list of groups and arrays located at the current level
- Returns:
a list of key names pointing to objects at the current level
- Return type:
list