coota 1.0.0b0

A powerful data-generating library.

COOTA

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What is COOTA

COOTA(Come Out Of Thin Air) is a powerful data-generating python library. By supporting generator nesting, it allows you to generate a variety of data that shows great randomness. It also supports making generators conform to a certain distribution.

Catalog

[TOC]

Installation

Python Library

Requires Python 3.x.

Windows / Mac OS

pip install coota

Linux

pip3 install coota

Application

Go to 👆🏻download page.

Tutorial

Demo programs can be found under the "tutorial" folder.

Quick Start

Generate a letter using a Generator.

from coota import *


generator = LetterGenerator()
print(generator.generate())

This returns a random letter, for example:

a

See all built-in generators.

Generate data in batches using GeneratorSequence.

from coota import *


string_length = 2
int_range_from = 0
int_range_to = 10 # not included, which means the generator returns a integer x that matches 0 ≤ x < 10
generator_a = StringGenerator(string_length)
generator_b = IntGenerator(start=int_range_from, stop=int_range_to)
generator_sequence = GeneratorSequence("String: ", generator_a, ", Integer: ", generator_b, n=10)
for data in generator_sequence:
    print(data)

This returns 10 groups of data.

String: Pf, Integer: 6
String: YL, Integer: 9
String: kl, Integer: 8
String: xC, Integer: 4
String: lo, Integer: 2
String: on, Integer: 4
String: uE, Integer: 0
String: or, Integer: 3
String: gj, Integer: 8
String: vl, Integer: 0

The default arguments can be generators. For example:

from coota import *


string_length = IntGenerator(start=1, stop=4)
int_range_from = 0
int_range_to = 10
generator_a = StringGenerator(string_length)
generator_b = IntGenerator(start=int_range_from, stop=int_range_to)
generator_sequence = GeneratorSequence("String: ", generator_a, ", Integer: ", generator_b, n=10)
for data in generator_sequence:
    print(data)

String: I, Integer: 5
String: kaK, Integer: 1
String: aCx, Integer: 3
String: I, Integer: 2
String: Ev, Integer: 4
String: RXc, Integer: 4
String: Gh, Integer: 3
String: z, Integer: 6
String: DO, Integer: 3
String: OL, Integer: 2

The nesting depth is not limited. Any default argument like string_length can be a generator. Global arguments like int_range_from and int_range_to can also be generators, but they won't be parsed.

Data Generation

Instantiate a generator.

Built-in generators:

coota.generator

• LetterGenerator
• StringGenerator
• NumberGenerator
• LetterAndNumberGenerator
• IntGenerator
• IntIterable

coota.preset.generator

• TimeGenerator
• EmailGenerator
• QQMailGenerator

The following takes the time generator as an example.

from coota.preset import *


generator = TimeGenerator(start="2022-4-12", stop="2022-5-12")
output = generator.generate()
print(type(output))
print(output)

<class 'datetime.datetime'>
2022-05-06 08:21:13

Documentation

Chooser

class Chooser(object):

abstract:choice()

This method specifies how the chooser selects an item.

@abstractmethod
def choice(self, x: Sequence) -> Any:

Name	Usage
x	The data source from which the chooser chooses.
return	A single item chosen from x.

abstract:choices()

This method specifies how the chooser selects a batch of items.

@abstractmethod
def choices(self, x: Sequence, n: int, weights: Sequence = None) -> Sequence:

Name	Usage
x	The data source from which the chooser chooses.
n	The number of choices.
weights	A list of weights for each item when randomly selected.
return	A list of items chosen from x.

Association

class Association(object):

__init__()

def __init__(self, the_other_generator: Generator):

Name	Usage
the_other_generator	The other generator associated with this generator. That generator must generate before this generator.

get_the_other_generator

def get_the_other_generator(self) -> Generator:

Name	Usage
return	The other generator.

abstract:associate()

This method specifies the association between the output of two generators.

@abstractmethod
def associate(self, generator: Any, the_other_generator_output: Any) -> Any:

Name	Usage
generator	The generator whose set_association() is called with the association given to.
the_other_generator_output	The output generated by the other generator.
return	Anything.

GeneratorOutput

class GeneratorOutput(object):

__init__()

def __init__(self, output: Any):

Name	Usage
output	The output.

get_output()

def get_output(self) -> Any:

Name	Usage
return	The output.

Generator

class Generator(object):

__init__()

def __init__(self, *default_args, **args):

Name	Usage
default_args	Given to make() when no arguments are given to generate(). For example, in a GeneratorSequence, generate() is called with no arguments, then the default_args will be given to make().
args	Global arguments for the generator.

_get_weights()

def _get_weights(self) -> Union[Sequence, None]:

Name	Usage
return	A list of weights for each item when randomly selected.

_set_weights()

def _set_weights(self, weights: Sequence) -> None:

Name	Usage
weights	A list of weights for each item when randomly selected, whose length must be the same as source returns.
return

_get_source_cache()

def _get_source_cache(self) -> Union[Sequence, None]:

Name	Usage
return	The cache of the source.

_set_source_cache()

def _set_source_cache(self, source_cache: Sequence) -> None:

Name	Usage
source_cahce	The cache of the source.
return

_get_last()

def _get_last(self) -> Any:

Name	Usage
return	Last generated data.

_set_last()

def _set_last(self, last: Any) -> None:

Name	Usage
last	Last generated data.
return

get_parseable()

def get_parseable(self) -> bool:

Name	Usage
return	Whether the generator can be parsed as an argument.

set_parseable()

def set_parseable(self, parseable: bool) -> None:

Name	Usage
parseable	Whether the generator can be parsed as an argument. If false, the generator will be recognized as an argument itself instead of being parsed into an actual output.
return

get_uc()

def get_uc(self) -> bool:

Name	Usage
return	Whether the generator uses the cache of the source.

set_uc()

def set_uc(self, use_cache: bool) -> None:

Name	Usage
use_cache	Whether the generator uses the cache of the source. If true, the generator will only call source() once and use the cache instead after that. It's true by default. Set it to false if your source is not always static.
return

get_args()

def get_args(self) -> dict:

Name	Usage
return	The global arguments of the generator.

get_arg()

def get_arg(self, name: str, required_type: type = object) -> Any:

Name	Usage
name	The argument's name.
required_type	The type of argument you require. If any type of argument is acceptable, set it to object which is also by default.
return	The argument's value. It can be None if the argument does not exist or is not of the same type as required.

get_arg_or_default()

def get_arg_or_default(self, name: str, default: Any, required_type: type = object) -> Any:

Name	Usage
name	The argument's name.
default	The default value.
required_type	The type of argument you require. If any type of argument is acceptable, set it to object which is also by default.
return	The argument's value. The default value will be returned if the argument does not exist or is not of the same type as required.

get_required_arg()

def get_required_arg(self, name: str, required_type: type = object) -> Any:

Name	Usage
name	The argument's name.
required_type	The type of argument you require. If any type of argument is acceptable, set it to object which is also by default.
return	The argument's value.

Exception	Case
AttributeError	The argument does not exist.
TypeError	The argument is not of the same type as required.

get_default_args()

def get_default_args(self) -> tuple:

Name	Usage
return	The default arguments to be given to make().

get_chooser()

def get_chooser(self) -> Chooser:

Name	Usage
return	The generator's chooser.

set_chooser()

def set_chooser(self, chooser: Chooser) -> None:

Name	Usage
chooser	Set the generator's chooser. A DefaultChooser is used by default. If you want to customize the behavior of choosing, you can create your own chooser object and set it in the generator.
return

get_association()

def get_association(self) -> Union[Associatoin, None]:

Name	Usage
return	The association with the other generator.

set_association()

def set_association(self, association: Association) -> None:

Name	Usage
association	The association with the other generator.
return

choice()

def choice(self) -> Any:

Name	Usage
return	One single item chosen from the source by the chooser.

choices()

def choices(self, n: int) -> Sequence:

Name	Usage
n	The number of items.
return	A batch of items chosen from the source by the chooser.

abstract:source()

This method specifies what data the generator may generate.

@abstractmethod
def source(self) -> Sequence:

Name	Usage
return	The original dataset from which the generator selects.

get_source()

def get_source(self) -> Sequence:

Name	Usage
return	The same as source() returns. If use_cache is true, returns the source cache instead.

fits()

def fits(self, distribution: Distribution, *args) -> None:

Name	Usage
distribution	The distribution to which the generator fits.
args	Optional arguments for the distribution.
return

abstract:make()

This method specifies how to generate data.

@abstractmethod
def make(self, *args) -> Any:

Name	Usage
args	Optional arguments.
return	Anything.

generate()

def generate(self, *args, parse: bool = True) -> Any:

Name	Usage
args	Optional arguments given to make().
parse	Whether to resolve the generator in parameters and return values. True: return an output. False: return the generator itself.
return	Anything.

output()

def output(self, *args, parse: bool = False) -> GeneratorOutput:

Name	Usage
args	Optional arguments given to make().
parse	Whether to resolve the generator in parameters and return values.
return	The return value of generate() wrapped as a GeneratorOutput.

IterableGenerator

An IterableGenerator is an ordered iterator, not a selector. It achieves ordering by adding a pointer to the generator.

class ItertableGenerator(Generator):

get_pointer()

def get_pointer(self) -> Any:

Name	Usage
return	The pointer.

set_pointer()

def set_pointer(self, pointer: Any) -> None:

Name	Usage
pointer	The pointer which is 0 in default.
return

choice()

def choice(self) -> Any:

Name	Usage
return	self.get_source()[pointer]. The pointer must be an integer when calling this method.

choices()

def choices(self, n: int) -> Sequence:

Name
n	The number of choices.
return	self.get_source()[pointer: pointer + n]. The pointer must be an integer when calling this method.

abstract:initialize()

This is a callback used to set initialization operations such as pointers.

@abstractmethod
def initialize(self) -> None:

Name	Usage
return

abstract:step()

This method specifies how the iterator iterates.

@abstractmethod
def step(self) -> bool:

Name	Usage
return	True: continue iteration. False: stop iteration.

Distribution

Distribution can adjust the probability that each item in the source is selected.

abstract:fits()

This method specifies how the probability of each item being selected is distributed.

@abstractmethod
def fits(self, loc: float, scale: float, size: int, *args) -> Sequence: pass

Name	Usage
loc	The most probable index.
scale	Standard deviation.
size	The length of the source.
args	Optional arguments.
return	A list of weights. For example, numpy.ndarray([1, 1.5, 4.0, 10]).