* changed queue to set in AC3

Changed queue to set in AC3 (as in the pseudocode of the original algorithm) to reduce the number of consistency-check due to the redundancy of the same arcs in queue. For example, on the harder1 configuration of the Sudoku CSP the number consistency-check has been reduced from 40464 to 12562!

* re-added test commented by mistake

* added the mentioned AC4 algorithm for constraint propagation

AC3 algorithm has non-optimal worst case time-complexity O(cd^3 ), while AC4 algorithm runs in O(cd^2) worst case time

* added doctest in Sudoku for AC4 and and the possibility of choosing the constant propagation algorithm in mac inference

* removed useless doctest for AC4 in Sudoku because AC4's tests are already present in test_csp.py

* added map coloring SAT problems

* fixed typo errors and removed unnecessary brackets

* reformulated the map coloring problem

* Revert "reformulated the map coloring problem"

This reverts commit 20ab0e5afa238a0556e68f173b07ad32d0779d3b.

* Revert "fixed typo errors and removed unnecessary brackets"

This reverts commit f743146c43b28e0525b0f0b332faebc78c15946f.

* Revert "added map coloring SAT problems"

This reverts commit 9e0fa550e85081cf5b92fb6a3418384ab5a9fdfd.

* Revert "removed useless doctest for AC4 in Sudoku because AC4's tests are already present in test_csp.py"

This reverts commit b3cd24c511a82275f5b43c9f176396e6ba05f67e.

* Revert "added doctest in Sudoku for AC4 and and the possibility of choosing the constant propagation algorithm in mac inference"

This reverts commit 6986247481a05f1e558b93b2bf3cdae395f9c4ee.

* Revert "added the mentioned AC4 algorithm for constraint propagation"

This reverts commit 03551fbf2aa3980b915d4b6fefcbc70f24547b03.

* added map coloring SAT problem

* fixed build error

* Revert "added map coloring SAT problem"

This reverts commit 93af259e4811ddd775429f8a334111b9dd9e268c.

* Revert "fixed build error"

This reverts commit 6641c2c861728f3d43d3931ef201c6f7093cbc96.

* added map coloring SAT problem

* removed redundant parentheses

* added Viterbi algorithm

* added monkey & bananas planning problem

* simplified condition in search.py

* added tests for monkey & bananas planning problem

* removed monkey & bananas planning problem

* Revert "removed monkey & bananas planning problem"

This reverts commit 9d37ae0def15b9e058862cb465da13d2eb926968.

* Revert "added tests for monkey & bananas planning problem"

This reverts commit 24041e9a1a0ab936f7a2608e3662c8efec559382.

* Revert "simplified condition in search.py"

This reverts commit 6d229ce9bde5033802aca29ad3047f37ee6d870d.

* Revert "added monkey & bananas planning problem"

This reverts commit c74933a8905de7bb569bcaed7230930780560874.

* defined the PlanningProblem as a specialization of a search.Problem & fixed typo errors

* fixed doctest in logic.py

* fixed doctest for cascade_distribution

* added ForwardPlanner and tests

* added __lt__ implementation for Expr

* added more tests

* renamed forward planner

* Revert "renamed forward planner"

This reverts commit c4139e50e3a75a036607f4627717d70ad0919554.

* renamed forward planner class & added doc

* added backward planner and tests

* fixed mdp4e.py doctests

* removed ignore_delete_lists_heuristic flag

* fixed heuristic for forward and backward planners

* added SATPlan and tests

* fixed ignore delete lists heuristic in forward and backward planners

* fixed backward planner and added tests

* updated doc

* Minor modifications in planning_angelic_search.ipynb and knowledge_FOIL.ipynb notebooks.

* created notebooks for GraphPlan, Total Order Planner and Partial Order Planner

* Added hierarchical search and tests

* Created notebook planning_hierarchical_search.ipynb

* Added making progress and tests, minor changes in decompose

* image for planning_hierarchical_search.ipynb

* Added angelic search to planning code

* Added unit tests for angelic search

* Created notebook planning_angelic_search.ipynb

* Fixed refinements function for HLAs

* Added PartialOrderPlanner

* Added doctests

* Fix doctests

* Added tests for PartialOrderPlanner methods

* Added test for PartialOrderPlanner

* Rerun planning.ipynb

* Added notebook section for TotalOrderPlanner

* Added image

* Added notebook section for PartialOrderPlanner

* Updated README.md

* Refactor double tennis problem

* Refactored test for double_tennis_problem

* Updated README.md

* Added notebook sections for job_shop_problem and double_tennis_problem

* Updated README.md

* Fixed refinements example

* Added go_to_sfo problem

* Rename TotalOrderPlanner

* Renamed PDDL to PlanningProblem

* Refactored HLA

* Refactors

* Refactored broken tests

* Cleaned up duplicated code

* Cleaned up duplicated code

* Added TotalOrderPlanner

* Linearize helper function

* Added tests for TotalOrderPlanner

* Readd sussman anomaly test

* PDDLs and Actions can now be defined using Exprs as well as Strings

* Minor refactors

* GraphPlan fixed

* Updated test_planning.py

* Added test for spare_tire

* Added test for graphplan

* Added shopping problem

* Added tests for shopping_problem

* Updated README.md

* Refactored planning notebook

* Completed shopping problem

* Refactors

* Updated notebook

* Updated test_planning.py

* Removed doctest temporarily

* Added planning graph image

* Added section on GraphPlan

* Updated README.md

* added have_cake_and_eat_cake_too

* renamed effect_neg to effect_rem

* added have_cake_and_eat_cake_too to readme

* added details to Problems in planning.ipynb

Added more information for the problems Air Cargo, Spare Tire, Three Block Tower, Have Cake and Eat Cake Too.

* removed a test from planning.py

A test for three block tower problem is written here. I have removed it.

* Style fixes

* minor style fix

* fixed a typo

* minor fixes

some sentence issues

* minor changes

* minor fixes

* added test case for CYK_parse

* added testcase for CYK_parse

* corrected spacing

* fixed issues like alignment, missing comma etc.

* test case for double tennis problem

* Update planning.py

removed commented print statements.

* test commit

* agents.ipynb

* agents.ipynb

* Fixed all the instances of issue #833

* minor fix and cleared change in agents.ipynb

Throw away the second argument returned by enumerate as we do not use it. Otherwise, name `_` arg simplify the rest of this function using the returned values rather than just indexes.

* Fix flake8 warnings

* Remove unnecessary #noqa

* Fix doctest

* Removed redundant condition

* moved gola_test inside function

* refactor goal_test()

* define HLA, Problem and implement 11.1

* add demonstration of job_shop_problem

* implementing 11.5

* adding test for refinement

* Exclude test files from flake8 check

* Fix flake8 for main files

* Add flake8 check to build

* Update utils.py

in pseudo code the sequence of arguments is   " WEIGHTED-SAMPLE-WITH-REPLACEMENT(N, S, W)"  

* Update utils.py

in pseudo code the sequence of arguments is " WEIGHTED-SAMPLE-WITH-REPLACEMENT(N, S, W)"  same must follow in function "particle_filtering" in the file probability.py

* Update learning.py

weight_sample_with_replacement sequence of args

* Update probability.py

 weighted_sample_with_replacement sequence of args

* Update search.py

* Update planning.py

added double_tennis_problem from chapter 11 , figure 11.10

* Update utils.py

added missing space after comma

* Update learning.py

added missing space after comma

* Update probability.py

added missing space after comma

* Update search.py

added missing space after comma

* Update planning.py

* Update planning.py

* Update planning.py

* Update planning.py

* Update planning.py

* Update planning.py

* Update test_agents.py

pep8 changes, showed flake8 errors

* Update test_agents.py

* Update test_agents.py

* Update test_agents.py

* Update test_text.py

added missing whitespace after comma

* Update utils.py

added space after comma

* Update search.py

added space after comma

* Update probability.py

added space after comma

* Update learning.py

added space after comma

* Update planning.py

added double_tennis_problem

* Update rl.py

In the pseudocode figure 21.8, the first 'if' starts with argument 's', which is the previous state, not s1(i.e, the current state).

* Update search.py

the 'uniform_cost_search' in notebook 'search-4e.ipynb' resembles more to the pseudocode in book.

* Update search.py

* Update search.py

* Update search.py

* Update README.md

* Update README.md

* Update README.md

* Update planning.py

* Update planning.py

added spaces after comma

* Update planning.py

* Update test_planning.py

added double_tennis_problem test

* Update test_planning.py

* Update logic.py

added fol_fc_ask from fig 9.3

* Update logic.py

* Update test_planning.py

* Update test_agents.py

pep8 changes, showed flake8 errors

* Update test_agents.py

* Update test_agents.py

* Update test_agents.py

* Update test_text.py

added missing whitespace after comma

* Update utils.py

added space after comma

* Update search.py

added space after comma

* Update probability.py

added space after comma

* Update learning.py

added space after comma

* Update planning.py

added double_tennis_problem

* Update rl.py

In the pseudocode figure 21.8, the first 'if' starts with argument 's', which is the previous state, not s1(i.e, the current state).

* Update search.py

the 'uniform_cost_search' in notebook 'search-4e.ipynb' resembles more to the pseudocode in book.

* Update search.py

* Update search.py

* Update search.py

* Update search.py

Commenting issues fixed (spacing and punctuation was off sometimes).

* Update agents.py

* Update canvas.py

Grammar

* Update grid.py

* Update learning.py

Added period

* Update logic.py

Fix quoting

* Update mdp.py

Fixed quoting

* Update nlp.py

Capitalization and punctuation fixes

* Update planning.py

* Update probability.py

* Update rl.py

'th' to 'the'

* Update search.py

* Update text.py

* Update utils.py

* Update utils.py

* Update utils.py

* Update learning.py

Typo

* Update utils.py

* Added implementation of the cake problem

* Added test for three_block_tower and fixed a bug in three_block_tower code

In the precondition positive list, I am not sure whether b!=x is the best way to represent the condition. IsNot(b, x) can be used instead.

* Minor docstring changes

* Added Spare Tire Problem

* Fixed a bug in substitute method of class Action

* Fixed minor typo in comment

* Added Action class for PDDL

* Added tests for Action class

* Changed doc string

* Added PDLL class

* Added Air-Cargo-problem

* Tested Air Cargo Problem

* Made Log Usage Consistent in text.py

* Added Explicit Imports from utils

Used tool 2to3 to finish the porting to Python 3 plus some fixes by
hand.