experta

Experta is a Python library for building expert systems strongly inspired by CLIPS.

from random import choice
from experta import *


class Light(Fact):
    """Info about the traffic light."""
    pass


class RobotCrossStreet(KnowledgeEngine):
    @Rule(Light(color='green'))
    def green_light(self):
        print("Walk")

    @Rule(Light(color='red'))
    def red_light(self):
        print("Don't walk")

    @Rule(AS.light << Light(color=L('yellow') | L('blinking-yellow')))
    def cautious(self, light):
        print("Be cautious because light is", light["color"])

>>> engine = RobotCrossStreet()
>>> engine.reset()
>>> engine.declare(Light(color=choice(['green', 'yellow', 'blinking-yellow', 'red'])))
>>> engine.run()
Be cautious because light is blinking-yellow

Migrating from Pyknow

Experta is a Pyknow fork. Just replace any pyknow references in your code/examples to experta and everything should work the same.

Examples

You can find some more examples on GitHub.

TODO

CHANGELOG

1.9.4

Resolved #10. Corner case in DepthStrategy in which the first activation of the agenda didn’t get removed.

1.9.3

Resolved #11 that was introduced with #7, that caused the same behavior under different conditions.

1.9.2

Resolved #7. In some situations last activation was removed right after entering the agenda.

1.9.1

Resolved #3. Rules should not be called with already retracted facts.

1.9.0

Drop Python 3.4 support.
Use setup.cfg to save all package metadata.

1.8.0-1.8.2

Rebranded to Experta.

1.7.0

Implemented the template system.
Replaced warnings by watchers messages.
Fixed freeze() with frozen objects.
Fixed unfreeze() with unfrozen objects.
Parametrized DefFacts via reset() kwargs.

1.6.0

Improved overall performance.

1.5.0

Added Python version 3.7 to tox.ini.
Monkey and bananas example.
Fixed bug, numeric index args gets repeated in a weird way introduced in 1.4.0.
Pass only the defined args in absence of kwargs.

1.4.0

Order integer facts keys after making a copy.
as_dict method for Fact.
freeze and unfreeze method documentation.
unfreeze method in pyknow.utils.
Zebra example from Clips.

1.3.0

pyknow.operator module.
Nested matching.
Added Talk ‘Sistemas Expertos en Python con PyKnow - PyConES 2017’ to docs folder.

1.2.0

Freeze fact values as the default behavior to address Issue #9.
Added pyknow.utils.anyof to mitigate Issue #7.
Raise RuntimeError if a fact value is modified after declare().
Added MATCH and AS objects.

1.1.1

Removing the borg optimization for P field constraints.
Use the hash of the check in the sorting of the nodes to always generate the same alpha part of the network.

1.1.0

Allow any kind of callable in Predicate Field Constraints (P()).

1.0.1

DNF of OR clause inside AND or Rule was implemented wrong.

1.0.0

RETE matching algorithm.
Better Rule decorator system.
Facts are dictionaries.
Documentation.

<1.0.0

Unestable API.
Wrong matching algorithm.
Bad performance
PLEASE DON’T USE THIS.

Release files for experta 1.9.4

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for experta 1.9.4
File	Size	Uploaded
experta-1.9.4.tar.gz	26.4 kB	Nov 16, 2019	Details

Built distribution (wheel)

Table of built distributions (wheels) for experta 1.9.4
File	Interpreter	ABI	Platform	Reset
experta-1.9.4-py3-none-any.whl 35.6 kB Nov 16, 2019	Python 3	none	any	Details

Total release size: 62.0 kB

Release files / experta-1.9.4.tar.gz

Download URL	experta-1.9.4.tar.gz
Size	26.4 kB
Tags	Source
SHA-256 checksum How to use checksums	`7c6ea687043b138f4ac7d3a8aea92aa60c02035e350c105a6bc142203fedc109`
BLAKE2b-256 checksum How to use checksums	`8b7c355d110bb687caa47d4205963d077abca92f2627bfefafc2115db96e7d58`
Upload date	Nov 16, 2019
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/2.0.0 pkginfo/1.5.0.1 requests/2.22.0 setuptools/41.6.0 requests-toolbelt/0.9.1 tqdm/4.38.0 CPython/3.7.5`

Release files / experta-1.9.4-py3-none-any.whl

Download URL	experta-1.9.4-py3-none-any.whl
Size	35.6 kB
Tags	Python 3
SHA-256 checksum How to use checksums	`c83d78d17305d9df502d6c3f14259f3b909278f3dd99f2494c0b83791ebe13c9`
BLAKE2b-256 checksum How to use checksums	`035dc06fad9dadbec34d95f548bca648ec0de2afd6f8eb2247194150ad38ee8f`
Upload date	Nov 16, 2019
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/2.0.0 pkginfo/1.5.0.1 requests/2.22.0 setuptools/41.6.0 requests-toolbelt/0.9.1 tqdm/4.38.0 CPython/3.7.5`