# `WaveformGeneratorDrift`

### *class* capymoa.stream.generator.WaveformGeneratorDrift[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/generator.py#L840)

Bases: [`MOAStream`](capymoa.stream.MOAStream.md#capymoa.stream.MOAStream)

An Waveform Generator Drift

```pycon
>>> from capymoa.stream.generator import WaveformGeneratorDrift
...
>>> stream = WaveformGeneratorDrift()
>>> stream.next_instance()
LabeledInstance(
    Schema(generators.WaveformGeneratorDrift -d 10),
    x=[3.787 3.658 5.136 ... 5.723 2.665 2.681],
    y_index=1,
    y_label='class2'
)
>>> stream.next_instance().x
array([ 0.54985074,  2.17089406,  0.6142235 ,  3.18809944, -1.81293483,
       -0.11717947, -1.77198821, -0.14927903, -0.49779111, -1.33272998,
       -0.38139892, -1.49682927,  1.49204371,  2.65344343,  4.25116434,
        3.39751393,  2.90259886,  4.21403878,  1.98411715,  3.33956917,
        4.08153654])
```

#### \_\_init_\_(instance_random_seed: [int](https://docs.python.org/3/builtins/functions.html#int) = 1, noise: [bool](https://docs.python.org/3/builtins/functions.html#bool) = False, number_of_attributes_with_drift: [int](https://docs.python.org/3/builtins/functions.html#int) = 10)[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/generator.py#L862)

Construct a WaveformGeneratorDrift Generator .

* **Parameters:**
  * **instance_random_seed** – Seed for random generation of instances, defaults to 1
  * **noise** – Adds noise for a total of 40 attributes
  * **number_of_attributes_with_drift** – Number of attributes with drift

#### \_\_iter_\_() → [Self](https://docs.python.org/3/library/typing.html#typing.Self)[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/_stream.py#L356)

Get an iterator over the stream.

This will NOT restart the stream if it has already been iterated over.
Please use the [`restart()`](#capymoa.stream.generator.WaveformGeneratorDrift.restart) method to restart the stream.

* **Yield:**
  An iterator over the stream.

#### \_\_next_\_() → \_AnyInstance[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/_stream.py#L366)

Get the next instance in the stream.

* **Returns:**
  The next instance in the stream.

#### cli_help() → [str](https://docs.python.org/3/builtins/stdtypes.html#str)[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/_stream.py#L466)

Return cli help string for the stream.

#### get_moa_stream() → InstanceStream | [None](https://docs.python.org/3/builtins/constants.html#None)[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/_stream.py#L502)

Get the MOA stream object if it exists.

#### get_schema() → [Schema](capymoa.stream.Schema.md#capymoa.stream.Schema)[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/_stream.py#L498)

Return the schema of the stream.

#### has_more_instances() → [bool](https://docs.python.org/3/builtins/functions.html#bool)[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/_stream.py#L474)

Return True if the stream have more instances to read.

#### next_instance() → \_AnyInstance[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/_stream.py#L478)

Return the next instance in the stream.

* **Raises:**
  [**ValueError**](https://docs.python.org/3/builtins/exceptions.html#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()[[source]](https://github.com/adaptive-machine-learning/CapyMOA/blob/3e255b1/src/capymoa/stream/_stream.py#L506)

Restart the stream to read instances from the beginning.