MIDict (Multi-Index Dict)
MIDict
is an ordered "dictionary" with multiple indices
where any index can serve as "keys" or "values",
capable of assessing multiple values via its powerful indexing syntax,
and suitable as a bidirectional/inverse dict (a drop-in replacement
for dict/OrderedDict in Python 2 & 3).
Features
- Multiple indices
- Multi-value indexing syntax
- Convenient indexing shortcuts
- Bidirectional/inverse dict
- Compatible with normal dict in Python 2 & 3
- Accessing keys via attributes
- Extended methods for multi-indices
- Additional APIs to handle indices
- Duplicate keys/values handling
Quickstart
name | uid | ip |
---|---|---|
jack | 1 | 192.1 |
tony | 2 | 192.2 |
The above table-like data set (with multiple columns/indices) can be represented using a MIDict
:
user = MIDict([['jack', 1, '192.1'], # list of items (rows of data)
['tony', 2, '192.2']],
['name', 'uid', 'ip']) # a list of index names
Access a key and get a value or a list of values (similar to a normal dict
):
user['jack'] == [1, '192.1']
Any index (column) can be used as the "keys" or "values" via the advanced
"multi-indexing" syntax d[index_key:key, index_value]
.
Both index_key
and index_value
can be a normal index name
or an int
(the order the index), and index_value
can also be a
tuple
, list
or slice
object to specify multiple values, e.g.:
user['name':'jack', 'uid'] == 1
user['ip':'192.1', 'name'] == 'jack'
user['name':'jack', ('uid', 'ip')] == [1, '192.1']
user[0:'jack', [1, 2]] == [1, '192.1']
user['name':'jack', 'uid':] == [1, '192.1']
The "multi-indexing" syntax also has convenient shortcuts:
user['jack'] == [1, '192.1']
user[:'192.1'] == ['jack', 1]
user['jack', :] == ['jack', 1, '192.1']
A MIDict
with 2 indices can be used as a bidirectional/inverse dict:
mi_dict = MIDict(jack=1, tony=2)
mi_dict['jack'] == 1 # forward indexing: d[key] -> value
mi_dict[:1] == 'jack' # backward/inverse indexing: d[:value] -> key
Documentation
See https://midict.readthedocs.io
Installation
pip install midict
PyPI repository: https://pypi.python.org/pypi/midict
Development
Source code: https://github.com/ShenggaoZhu/midict
Report issues: https://github.com/ShenggaoZhu/midict/issues/new
Testing
python tests/tests.py
Tested with both Python 2.7 and Python 3,3, 3.4, 3.5.