Demos

py-trees-demo-action-behaviour

A py_trees demo.

class py_trees.demos.action.Action(name: str)

Bases: Behaviour

Demonstrates the at-a-distance style action behaviour.

This behaviour connects to a separately running process (initiated in setup()) and proceeeds to work with that subprocess to initiate a task and monitor the progress of that task at each tick until completed. While the task is running the behaviour returns RUNNING.

On completion, the the behaviour returns with success or failure (depending on success or failure of the task itself).

Key point - this behaviour itself should not be doing any work!

__init__(name: str)

Configure the name of the behaviour.

initialise() → None

Reset a counter variable.

setup(**kwargs: int) → None

Kickstart the separate process this behaviour will work with.

Ordinarily this process will be already running. In this case, setup is usually just responsible for verifying it exists.

terminate(new_status: Status) → None

Nothing to clean up in this example.

update() → Status

Increment the counter, monitor and decide on a new status.

py_trees.demos.action.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.action.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.action.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.action.main() → None

Entry point for the demo script.

py_trees.demos.action.planning(pipe_connection: Connection) → None

Emulate a (potentially) long running external process.

Args:

pipe_connection: connection to the planning process

py-trees-demo-behaviour-lifecycle

A py_trees demo.

. argparse::

module:

py_trees.demos.lifecycle

func:

command_line_argument_parser

prog:

py-trees-demo-behaviour-lifecycle

class py_trees.demos.lifecycle.Counter(name: str = 'Counter')

Bases: Behaviour

Simple counting behaviour.

• Increments a counter from zero at each tick

• Finishes with success if the counter reaches three

• Resets the counter in the initialise() method.

__init__(name: str = 'Counter')

Configure the name of the behaviour.

initialise() → None

Reset a counter variable.

setup(**kwargs: int) → None

No delayed initialisation required for this example.

terminate(new_status: Status) → None

Nothing to clean up in this example.

update() → Status

Increment the counter and decide on a new status.

py_trees.demos.lifecycle.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.lifecycle.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.lifecycle.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.lifecycle.main() → None

Entry point for the demo script.

py-trees-demo-blackboard

A py_trees demo.

Console Screenshot

class py_trees.demos.blackboard.BlackboardWriter(name: str)

Bases: Behaviour

Write some more interesting / complex types to the blacbkoard.

__init__(name: str)

Set up the blackboard.

Args:

name: behaviour name

update() → Status

Write a dictionary to the blackboard.

This beaviour always returns SUCCESS.

class py_trees.demos.blackboard.Nested

Bases: object

A more complex object to interact with on the blackboard.

__init__() → None

Initialise variables to some arbitrary defaults.

__str__() → str

Return str(self).

__weakref__

list of weak references to the object (if defined)

class py_trees.demos.blackboard.ParamsAndState(name: str)

Bases: Behaviour

Parameter and state storage on the blackboard.

This behaviour demonstrates the usage of namespaces and multiple clients to perform getting and setting of parameters and state in a concise and convenient manner.

__init__(name: str)

Set up separate blackboard clients for parameters and state.

Args:

name: behaviour name

initialise() → None

Initialise speed from the stored parameter variable on the blackboard.

update() → Status

Check speed and either increment, or complete if it has reached a threshold.

Returns:

RUNNING if incrementing, SUCCESS otherwise.

py_trees.demos.blackboard.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.blackboard.create_root() → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.blackboard.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.blackboard.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.blackboard.main() → None

Entry point for the demo script.

py-trees-demo-blackboard-namespaces

A py_trees demo.

Console Screenshot

py_trees.demos.blackboard_namespaces.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.blackboard_namespaces.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.blackboard_namespaces.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.blackboard_namespaces.main() → None

Entry point for the demo script.

py-trees-demo-blackboard-remappings

A py_trees demo.

Console Screenshot

class py_trees.demos.blackboard_remappings.Remap(name: str, remap_to: Dict[str, str])

Bases: Behaviour

Custom writer that submits a more complicated variable to the blackboard.

__init__(name: str, remap_to: Dict[str, str])

Set up the blackboard and remap variables.

Args:

name: behaviour name remap_to: remappings (from variable name to variable name)

update() → Status

Write a dictionary to the blackboard.

This beaviour always returns SUCCESS.

py_trees.demos.blackboard_remappings.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.blackboard_remappings.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.blackboard_remappings.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.blackboard_remappings.main() → None

Entry point for the demo script.

py-trees-demo-context-switching

A py_trees demo.

class py_trees.demos.context_switching.ContextSwitch(name: str = 'ContextSwitch')

Bases: Behaviour

An example of a context switching class.

This class sets (in initialise()) and restores a context (in terminate()). Use in parallel with a sequence/subtree that does the work while in this context.

Attention

Simply setting a pair of behaviours (set and reset context) on either end of a sequence will not suffice for context switching. In the case that one of the work behaviours in the sequence fails, the final reset context switch will never trigger.

__init__(name: str = 'ContextSwitch')

Initialise with a behaviour name.

initialise() → None

Backup and set a new context.

terminate(new_status: Status) → None

Restore the context with the previously backed up context.

update() → Status

Just returns RUNNING while it waits for other activities to finish.

py_trees.demos.context_switching.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.context_switching.create_root() → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.context_switching.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.context_switching.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.context_switching.main() → None

Entry point for the demo script.

py-trees-demo-dot-graphs

A py_trees demo.

py_trees.demos.dot_graphs.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.dot_graphs.create_tree(level: str) → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.dot_graphs.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.dot_graphs.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.dot_graphs.main() → None

Entry point for the demo script.

py-trees-demo-either-or

A py_trees demo.

py_trees.demos.either_or.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.either_or.create_root() → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.either_or.description(root: Behaviour) → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.either_or.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.either_or.main() → None

Entry point for the demo script.

py_trees.demos.either_or.post_tick_handler(snapshot_visitor: SnapshotVisitor, behaviour_tree: BehaviourTree) → None

Print data about the part of the tree visited.

Args:

snapshot_handler: gather data about the part of the tree visited behaviour_tree: tree to gather data from

py_trees.demos.either_or.pre_tick_handler(behaviour_tree: BehaviourTree) → None

Print a banner with current tick count prior to ticking the tree.

Args:

behaviour_tree: the tree to tick (used to fetch the count number)

py-trees-demo-eternal-guard

A py_trees demo.

py_trees.demos.eternal_guard.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.eternal_guard.create_root() → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.eternal_guard.description(root: Behaviour) → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.eternal_guard.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.eternal_guard.main() → None

Entry point for the demo script.

py_trees.demos.eternal_guard.post_tick_handler(snapshot_visitor: SnapshotVisitor, behaviour_tree: BehaviourTree) → None

Print data about the part of the tree visited.

Args:

snapshot_handler: gather data about the part of the tree visited behaviour_tree: tree to gather data from

py_trees.demos.eternal_guard.pre_tick_handler(behaviour_tree: BehaviourTree) → None

Print a banner with current tick count prior to ticking the tree.

Args:

behaviour_tree: the tree to tick (used to fetch the count number)

py-trees-demo-logging

A py_trees demo.

py_trees.demos.logging.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.logging.create_tree() → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.logging.description(root: Behaviour) → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.logging.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.logging.logger(snapshot_visitor: DisplaySnapshotVisitor, behaviour_tree: BehaviourTree) → None

Log the tree (relevant parts thereof) to a yaml file.

Use as a post-tick handler for a tree.

py_trees.demos.logging.main() → None

Entry point for the demo script.

py-trees-demo-selector

A py_trees demo.

py_trees.demos.selector.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.selector.create_root() → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.selector.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.selector.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.selector.main() → None

Entry point for the demo script.

py-trees-demo-sequence

A py_trees demo.

py_trees.demos.sequence.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.sequence.create_root() → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.sequence.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.sequence.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.sequence.main() → None

Entry point for the demo script.

py-trees-demo-tree-stewardship

A py_trees demo.

class py_trees.demos.stewardship.Finisher

Bases: Behaviour

Gathers blackboard data from other behaviours and prints a summary.

To be used at the end of the tree run.

__init__() → None

Set up the blackboard.

update() → Status

Fetch blackboard variables and print a summary.

Returns:

Always returns SUCCESS.

class py_trees.demos.stewardship.PeriodicSuccess

Bases: Periodic

Write the period from Periodic as a variable on the blackboard.

__init__() → None

Initialise Periodic and set up the blackboard.

update() → Status

Run the Periodic update and write to blackboard.

Returns:

Returns the Status of Periodic

class py_trees.demos.stewardship.SuccessEveryN

Bases: SuccessEveryN

Add a blackboard counter to SuccessEveryN.

__init__() → None

Set up the blackboard.

update() → Status

Run the SuccessEveryN update and write to blackboard.

Returns:

Returns the Status of SuccessEveryN

py_trees.demos.stewardship.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.stewardship.create_tree() → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.stewardship.description() → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.stewardship.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.stewardship.main() → None

Entry point for the demo script.

py_trees.demos.stewardship.pre_tick_handler(behaviour_tree: BehaviourTree) → None

Generate a simple pre-tick banner printing to stdout.

py-trees-demo-pick-up-where-you-left-off

A py_trees demo.

py_trees.demos.pick_up_where_you_left_off.command_line_argument_parser() → ArgumentParser

Process command line arguments.

Returns:

the argument parser

py_trees.demos.pick_up_where_you_left_off.create_root() → Behaviour

Create the root behaviour and it’s subtree.

Returns:

the root behaviour

py_trees.demos.pick_up_where_you_left_off.description(root: Behaviour) → str

Print description and usage information about the program.

Returns:

the program description string

py_trees.demos.pick_up_where_you_left_off.epilog() → str | None

Print a noodly epilog for –help.

Returns:

the noodly message

py_trees.demos.pick_up_where_you_left_off.main() → None

Entry point for the demo script.

py_trees.demos.pick_up_where_you_left_off.post_tick_handler(snapshot_visitor: SnapshotVisitor, behaviour_tree: BehaviourTree) → None

Print an ascii tree with the current snapshot status.

py_trees.demos.pick_up_where_you_left_off.pre_tick_handler(behaviour_tree: BehaviourTree) → None

Print a banner immediately before every tick of the tree.

Args:

behaviour_tree (BehaviourTree): the tree custodian