ARFFStream

class capymoa.stream.ARFFStream

Bases: MOAStream[_AnyInstance]

A datastream originating from an ARFF file.

__init__(

path: str | Path,

CLI: str | None = None,

class_index: int = -1,

)

Construct an ARFFStream object from a file path.

Parameters:

• path – A filepath

• CLI – Additional command line arguments to pass to the MOA stream.

__iter__() → Iterator[_AnyInstance]

Get an iterator over the stream.

This will NOT restart the stream if it has already been iterated over. Please use the restart() method to restart the stream.

Yield:

An iterator over the stream.

__next__() → _AnyInstance

Get the next instance in the stream.

Returns:

The next instance in the stream.

cli_help() → str

Return cli help string for the stream.

get_moa_stream() → InstanceStream | None

Get the MOA stream object if it exists.

get_schema() → Schema

Return the schema of the stream.

has_more_instances() → bool

Return True if the stream have more instances to read.

next_instance() → _AnyInstance

Return the next instance in the stream.

Raises:

ValueError – If the machine learning task is neither a regression nor a classification task.

Returns:

A labeled instances or a regression depending on the schema.

restart()

Restart the stream to read instances from the beginning.