fiftyone.core.stages.Flatten

class documentation

class Flatten(ViewStage): (source)

Constructor: Flatten(stages)

Returns a flattened view that contains all samples in a dynamic grouped collection.

Examples:

import fiftyone as fo
import fiftyone.zoo as foz
from fiftyone import ViewField as F

dataset = foz.load_zoo_dataset("cifar10", split="test")

# Group samples by ground truth label
grouped_view = dataset.take(1000).group_by("ground_truth.label")
print(len(grouped_view))  # 10

# Return a flat view that contains 10 samples from each class
stage = fo.Flatten(fo.Limit(10))
flat_view = grouped_view.add_stage(stage)
print(len(flat_view))  # 100

Parameters
stages	a `ViewStage` or list of `ViewStage` instances to apply to each group's samples while flattening

Method	`__init__`	Undocumented
Method	`get_media_type`	Returns the media type outputted by this stage when applied to the given collection, if and only if it is different from the input type.
Method	`to_mongo`	Returns the MongoDB aggregation pipeline for the stage.
Method	`validate`	Validates that the stage can be applied to the given collection.
Property	`outputs_dynamic_groups`	Whether this stage outputs or flattens dynamic groups.
Property	`stages`	Stage(s) to apply to each group's samples while flattening.
Class Method	`_params`	Returns a list of JSON dicts describing the stage's supported parameters.
Method	`_kwargs`	Returns a list of `[name, value]` lists describing the parameters of this stage instance.
Instance Variable	`_pipeline`	Undocumented
Instance Variable	`_stages`	Undocumented
Instance Variable	`_stages_kwargs`	Undocumented

Inherited from ViewStage:

Method	`__eq__`	Undocumented
Method	`__repr__`	Undocumented
Method	`__str__`	Undocumented
Method	`get_edited_fields`	Returns a list of names of fields or embedded fields that may have been edited by the stage, if any.
Method	`get_excluded_fields`	Returns a list of fields that have been excluded by the stage, if any.
Method	`get_filtered_fields`	Returns a list of names of fields or embedded fields that contain arrays have been filtered by the stage, if any.
Method	`get_group_expr`	Returns the dynamic group expression for the given stage, if any.
Method	`get_group_media_types`	Returns the group media types outputted by this stage, if any, when applied to the given collection, if and only if they are different from the input collection.
Method	`get_selected_fields`	Returns a list of fields that have been selected by the stage, if any.
Method	`load_view`	Loads the `fiftyone.core.view.DatasetView` containing the output of the stage.
Property	`flattens_groups`	Whether this stage flattens groups into a non-grouped collection.
Property	`has_view`	Whether this stage's output view should be loaded via `load_view` rather than appending stages to an aggregation pipeline via `to_mongo`.
Class Method	`_from_dict`	Creates a `ViewStage` instance from a serialized JSON dict representation of it.
Method	`_needs_frames`	Whether the stage requires frame labels of video samples to be attached.
Method	`_needs_group_slices`	Whether the stage requires group slice(s) to be attached.
Method	`_serialize`	Returns a JSON dict representation of the `ViewStage`.
Instance Variable	`_uuid`	Undocumented

def __init__(self, stages=None): (source) ¶

Undocumented

def get_media_type(self, sample_collection): (source) ¶

overrides fiftyone.core.stages.ViewStage.get_media_type

Returns the media type outputted by this stage when applied to the given collection, if and only if it is different from the input type.

Parameters
sample_collection	the `fiftyone.core.collections.SampleCollection` to which the stage is being applied
Returns
the media type, or `None` if the stage does not change the type

def to_mongo(self, sample_collection): (source) ¶

overrides fiftyone.core.stages.ViewStage.to_mongo

Returns the MongoDB aggregation pipeline for the stage.

Only usable if has_view is False.

Parameters
sample_collection	the `fiftyone.core.collections.SampleCollection` to which the stage is being applied
Returns
a MongoDB aggregation pipeline (list of dicts)

def validate(self, sample_collection): (source) ¶

overrides fiftyone.core.stages.ViewStage.validate

Validates that the stage can be applied to the given collection.

Parameters
sample_collection	a `fiftyone.core.collections.SampleCollection`
Raises
`ViewStageError`	if the stage cannot be applied to the collection

@property
outputs_dynamic_groups = (source) ¶

overrides fiftyone.core.stages.ViewStage.outputs_dynamic_groups

Whether this stage outputs or flattens dynamic groups.

The possible return values are:

True: this stage dynamically groups the input collection
False: this stage flattens dynamic groups
None: this stage does not change group status

@property
stages = (source) ¶

Stage(s) to apply to each group's samples while flattening.

@classmethod
def _params(cls): (source) ¶

overrides fiftyone.core.stages.ViewStage._params

Returns a list of JSON dicts describing the stage's supported parameters.

Returns
a list of JSON dicts

def _kwargs(self): (source) ¶

overrides fiftyone.core.stages.ViewStage._kwargs

Returns a list of [name, value] lists describing the parameters of this stage instance.

Returns
a list of `[name, value]` lists

_pipeline = (source) ¶

Undocumented

_stages = (source) ¶

Undocumented

_stages_kwargs = (source) ¶

Undocumented