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An intelligent navigable dictionary

🚧– WIP – this is an early version of a project in development. Please use it and fork it and create issues and feature requests.

This module defines the NavigableDict (aka. navdict), which is a dictionary that is dot-navigable and has some special features to autoload files.

The information that is in the NavigableDict can be navigated in two different ways. First, the navdict is a dictionary, so all information can be accessed by keys as in the following example.

>>> setup = NavigableDict({"gse": {"hexapod": {"ID": 42, "calibration": [0,1,2,3,4,5]}}})
>>> setup["gse"]["hexapod"]["ID"]
42

Second, each of the keys is also available as an attribute of the NavigableDict and that makes it possible to navigate the navdict with dot-notation:

>>> id = setup.gse.hexapod.ID

If you want to know which keys you can use to navigate the navdict, use the keys() method.

>>> setup.gse.hexapod.keys()
dict_keys(['ID', 'calibration'])
>>> setup.gse.hexapod.calibration
[0, 1, 2, 3, 4, 5]

To get a full printout of the navdict, you can use the print method from the rich package. Be careful, because this can print out a lot of information when a full configuration is loaded.

>>> from rich import print
>>> print(setup)
NavigableDict
└── gse
    └── hexapod
        ├── ID: 42
        └── calibration: [0, 1, 2, 3, 4, 5]

Special Values

Some of the information in the navdict is interpreted in a special way, i.e. some values are processed before returning. Examples are the classes and calibration/data files. The following values are treated special if they start with:

  • class//: instantiate the class and return the object
  • factory//: instantiates a factory and executes its create() method
  • csv//: load the CSV file and return a numpy array
  • yaml//: load the YAML file and return a dictionary
  • int-enum//: dynamically create the enumeration and return the Enum object

Data Files

Some information is too large to add to the navdict as such and should be loaded from a data file. Examples are calibration files, flat-fields, temperature conversion curves, etc.

The navdict will automatically load the file when you access a key that contains a value that starts with csv// or yaml//.

>>> setup = navdict({
...     "instrument": {"coeff": "csv//cal_coeff_1234.csv"}
... })
>>> setup.instrument.coeff[0, 4]
5.0

Note: the resource location is always relative to the current location XXXX