Set up AutoML to train a time-series forecasting model with SDK and CLI

Article
10/11/2024

APPLIES TO: Azure CLI ml extension v2 (current) Python SDK azure-ai-ml v2 (current)

AutoML uses standard machine learning models along with well-known time series models to create forecasts. This approach incorporates historical information about the target variable, user-provided features in the input data, and automatically engineered features. Model search algorithms work to find a model with the best predictive accuracy. For more information, see forecasting methodology and model search.

In this article, you learn how to set up AutoML for time-series forecasting with Azure Machine Learning automated ML in the Azure Machine Learning Python SDK.

To do so, you:

Prepare data for training.
Configure specific time-series parameters in a Forecasting Job.
Orchestrate training, inference, and model evaluation using components and pipelines.

For a low code experience, see Tutorial: Forecast demand with automated machine learning. This resource is a time-series forecasting example that uses automated ML in the Azure Machine Learning studio.

Prerequisites

An Azure Machine Learning workspace. To create a workspace, see Create workspace resources.
The ability to launch AutoML training jobs. For more information, see how-to guide for setting up AutoML.

Training and validation data

Input data for AutoML forecasting must contain a valid time series in tabular format. Each variable must have its own corresponding column in the data table. AutoML requires at least two columns: a time column that represents the time axis and the *target column, which is the quantity to forecast. Other columns can serve as predictors. For more information, see how AutoML uses your data.

Important

When you train a model for forecasting future values, ensure that all the features used in training can be used when running predictions for your intended horizon.

For example, a feature for current stock price could massively increase training accuracy. However, if you intend to forecast with a long horizon, you might not be able to accurately predict future stock values that correspond to future time-series points. Model accuracy could suffer.

AutoML forecasting jobs require that your training data is represented as an MLTable object. An MLTable specifies a data source and steps for loading the data. For more information and use cases, see Working with tables in Azure Machine Learning. As an example, suppose your training data is contained in a CSV file in a local directory, ./train_data/timeseries_train.csv.

Python SDK
Azure CLI

You can create an MLTable using the mltable Python SDK as in the following example:

import mltable

paths = [
    {'file': './train_data/timeseries_train.csv'}
]

train_table = mltable.from_delimited_files(paths)
train_table.save('./train_data')

This code creates a new file, ./train_data/MLTable, which contains the file format and loading instructions.

In order to start the training job, define an input data object by using the Azure Machine Learning Python SDK as follows:

from azure.ai.ml.constants import AssetTypes
from azure.ai.ml import Input

# Training MLTable defined locally, with local data to be uploaded
my_training_data_input = Input(
    type=AssetTypes.MLTABLE, path="./train_data"
)

You can define a new MLTable by copying the following YAML text to a new file, ./train_data/MLTable:

$schema: https://azuremlschemas.azureedge.net/latest/MLTable.schema.json

type: mltable
paths:
    - file: ./timeseries_train.csv

transformations:
    - read_delimited:
        delimiter: ','
        encoding: ascii

Begin building the YAML configuration file for the AutoML job with the training data specified as shown in the following example:

$schema: https://azuremlsdk2.blob.core.chinacloudapi.cn/preview/0.0.1/autoMLJob.schema.json
type: automl

experiment_name: cli-v2-automl-forecasting-job
description: A time series forecasting AutoML job
task: forecasting

# training data MLTable for the AutoML job
training_data:
    path: "./train_data"
    type: mltable

validation_data:
    # optional validation data

compute: # compute for training job
primary_metric: # primary metric  

target_column_name: # target column name
n_cross_validations: # cv setting

limits:
    # limit settings

forecasting:
    # forecasting specific settings

training:
    # training settings

Add more detail to this configuration in subsequent sections of this how-to guide. In this example, the location is ./automl-forecasting-job.yml.

You specify validation data in a similar way. Create a MLTable and specify a validation data input. Alternatively, if you don't supply validation data, AutoML automatically creates cross-validation splits from your training data to use for model selection. For more information, see forecasting model selection. For more information about how much training data you need, see training data length requirements.

Learn more about how AutoML applies cross validation to prevent over fitting.

Compute to run experiment

AutoML uses Azure Machine Learning Compute, which is a fully managed compute resource, to run the training job. Create a compute cluster named cpu-compute.

Python SDK
Azure CLI

from azure.ai.ml.entities import AmlCompute

# specify aml compute name.
cpu_compute_target = "cpu-cluster"

try:
    ml_client.compute.get(cpu_compute_target)
except Exception:
    print("Creating a new cpu compute target...")
    compute = AmlCompute(
        name=cpu_compute_target, size="STANDARD_D2_V2", min_instances=0, max_instances=4
    )
    ml_client.compute.begin_create_or_update(compute).result()

You can create a new compute called cpu-compute with the following CLI command:

az ml compute create -n cpu-compute --type amlcompute --min-instances 0 --max-instances 4

Reference this compute in the job definition as follows:

$schema: https://azuremlsdk2.blob.core.chinacloudapi.cn/preview/0.0.1/autoMLJob.schema.json
type: automl

experiment_name: cli-v2-automl-forecasting-job
description: A time series forecasting AutoML job
task: forecasting

# training data MLTable for the AutoML job
training_data:
    path: "./train_data"
    type: mltable

# compute for the training job to use 
compute: azureml:cpu-compute

primary_metric: # primary metric  

target_column_name: # target column name
n_cross_validations: # cv setting

limits:
    # limit settings

forecasting:
    # forecasting specific settings

training:
    # training settings

You use the automl factory functions to configure forecasting jobs in the Python SDK. The following example shows how to create a forecasting job by setting the primary metric and set limits on the training run:

from azure.ai.ml import automl

# note that the below is a code snippet -- you might have to modify the variable values to run it successfully
forecasting_job = automl.forecasting(
    compute="cpu-compute",
    experiment_name="sdk-v2-automl-forecasting-job",
    training_data=my_training_data_input,
    target_column_name=target_column_name,
    primary_metric="normalized_root_mean_squared_error",
    n_cross_validations="auto",
)

# Limits are all optional
forecasting_job.set_limits(
    timeout_minutes=120,
    trial_timeout_minutes=30,
    max_concurrent_trials=4,
)

Configure general properties of the AutoML job, including:

The primary metric
The name of the target column in the training data
The cross-validation settings
Resource limits on the job

For more information, see the forecasting job, training parameters, and limits.

$schema: https://azuremlsdk2.blob.core.chinacloudapi.cn/preview/0.0.1/autoMLJob.schema.json
type: automl

experiment_name: cli-v2-automl-forecasting-job
description: A time series forecasting AutoML job
task: forecasting

training_data:
    path: "./train_data"
    type: mltable

compute: azureml:cpu-compute

# settings for primary metric, target/label column name and CV
primary_metric: normalized_root_mean_squared_error
target_column_name: <target_column_name>
n_cross_validations: auto

# settings for training job limits on time, concurrency, and others
limits:
    timeout_minutes: 120
    trial_timeout_minutes: 30
    max_concurrent_trials: 4

forecasting:
    # forecasting specific settings

training:
    # training settings

Forecast job settings

Forecasting tasks have many settings that are specific to forecasting. The most basic of these settings are the name of the time column in the training data and the forecast horizon.

Python SDK
Azure CLI

Use the ForecastingJob methods to configure these settings:

# Forecasting specific configuration
forecasting_job.set_forecast_settings(
    time_column_name=time_column_name,
    forecast_horizon=24
)

These settings are configured in the forecasting section of the job YAML:

$schema: https://azuremlsdk2.blob.core.chinacloudapi.cn/preview/0.0.1/autoMLJob.schema.json
type: automl

experiment_name: cli-v2-automl-forecasting-job
description: A time series forecasting AutoML job
task: forecasting

training_data:
    path: "./train_data"
    type: mltable

compute: azureml:cpu-compute

primary_metric: normalized_root_mean_squared_error
target_column_name: <target_column_name>
n_cross_validations: auto

limits:
    timeout_minutes: 120
    trial_timeout_minutes: 30
    max_concurrent_trials: 4

# forecasting specific settings
# Set the horizon to 24 for this example, the horizon generally depends on the business scenario
forecasting:
    time_column_name: <time_column_name>
    forecast_horizon: 24

training:
    # training settings

The time column name is a required setting. You should generally set the forecast horizon according to your prediction scenario. If your data contains multiple time series, you can specify the names of the time series ID columns. These columns, when grouped, define the individual series. For example, suppose that you have data that consists of hourly sales from different stores and brands. The following sample shows how to set the time series ID columns assuming that the data contains columns named store and brand:

Python SDK
Azure CLI

# Forecasting specific configuration
# Add time series IDs for store and brand
forecasting_job.set_forecast_settings(
    ...,  # other settings
    time_series_id_column_names=['store', 'brand']
)

# forecasting specific settings
# Add time series IDs for store and brand
forecasting:
    # other settings
    time_series_id_column_names: ["store", "brand"]

AutoML tries to automatically detect time series ID columns in your data if none is specified.

Other settings are optional and reviewed in the next section.

Optional forecasting job settings

Optional configurations are available for forecasting tasks, such as enabling deep learning and specifying a target rolling window aggregation. A complete list of parameters is available in the reference documentation documentation.

Model search settings

There are two optional settings that control the model space where AutoML searches for the best model: allowed_training_algorithms and blocked_training_algorithms. To restrict the search space to a given set of model classes, use the allowed_training_algorithms parameter as in the following sample:

Python SDK
Azure CLI

# Only search ExponentialSmoothing and ElasticNet models
forecasting_job.set_training(
    allowed_training_algorithms=["ExponentialSmoothing", "ElasticNet"]
)

$schema: https://azuremlsdk2.blob.core.chinacloudapi.cn/preview/0.0.1/autoMLJob.schema.json
type: automl

experiment_name: cli-v2-automl-forecasting-job
description: A time series forecasting AutoML job
task: forecasting

training_data:
    path: "./train_data"
    type: mltable

compute: azureml:cpu-compute

primary_metric: normalized_root_mean_squared_error
target_column_name: <target_column_name>
n_cross_validations: auto

limits:
    timeout_minutes: 120
    trial_timeout_minutes: 30
    max_concurrent_trials: 4

forecasting:
    time_column_name: <time_column_name>
    forecast_horizon: 24

# training settings
# Only search ExponentialSmoothing and ElasticNet models
training:
    allowed_training_algorithms: ["ExponentialSmoothing", "ElasticNet"]
    # other training settings

In this case, the forecasting job only searches over Exponential Smoothing and Elastic Net model classes. To remove a given set of model classes from the search space, use the blocked_training_algorithms as in the following sample:

Python SDK
Azure CLI

# Search over all model classes except Prophet
forecasting_job.set_training(
    blocked_training_algorithms=["Prophet"]
)

# training settings
# Search over all model classes except Prophet
training:
    blocked_training_algorithms: ["Prophet"]
    # other training settings

The job searches over all model classes except Prophet. For a list of forecasting model names that are accepted in allowed_training_algorithms and blocked_training_algorithms, see training properties. You can apply either but not both allowed_training_algorithms and blocked_training_algorithms to a training run.

Enable deep learning

AutoML ships with a custom deep neural network (DNN) model called TCNForecaster. This model is a temporal convolutional network (TCN), that applies common imaging task methods to time series modeling. One-dimensional "causal" convolutions form the backbone of the network and enable the model to learn complex patterns over long durations in the training history. For more information, see Introduction to TCNForecaster.

The TCNForecaster often achieves higher accuracy than standard time series models when there are thousands or more observations in the training history. However, it also takes longer to train and sweep over TCNForecaster models due to their higher capacity.

You can enable the TCNForecaster in AutoML by setting the enable_dnn_training flag in the training configuration as follows:

Python SDK
Azure CLI

# Include TCNForecaster models in the model search
forecasting_job.set_training(
    enable_dnn_training=True
)

# training settings
# Include TCNForecaster models in the model search
training:
    enable_dnn_training: true
    # other training settings

By default, TCNForecaster training is limited to a single compute node and a single GPU, if available, per model trial. For large data scenarios, we recommend distributing each TCNForecaster trial over multiple cores/GPUs and nodes. For more information and code samples, see distributed training.

To enable DNN for an AutoML experiment created in the Azure Machine Learning studio, see the task type settings in the studio UI how-to.

Note

When you enable DNN for experiments created with the SDK, best model explanations are disabled.
DNN support for forecasting in Automated Machine Learning is not supported for runs initiated in Databricks.
We recommend GPU compute types when DNN training is enabled.

Lag and rolling window features

Recent values of the target are often impactful features in a forecasting model. Accordingly, AutoML can create time-lagged and rolling window aggregation features to potentially improve model accuracy.

Consider an energy demand forecasting scenario where weather data and historical demand are available. The table shows resulting feature engineering that occurs when window aggregation is applied over the most recent three hours. Columns for minimum, maximum, and sum are generated on a sliding window of three hours based on the defined settings. For instance, for the observation valid on September 8, 2017 4:00am, the maximum, minimum, and sum values are calculated using the demand values for September 8, 2017 1:00AM - 3:00AM. This window of three hours shifts along to populate data for the remaining rows. For more information and examples, see the Lagged features for time series forecasting in AutoML.

Screenshot shows the target rolling window with values for Demand called out.

You can enable lag and rolling window aggregation features for the target by setting the rolling window size and the lag orders you want to create. The window size was three in the previous example. You can also enable lags for features with the feature_lags setting. In the following example, all of these settings are auto so that AutoML automatically determines settings by analyzing the correlation structure of your data:

Python SDK
Azure CLI

forecasting_job.set_forecast_settings(
    ...,  # other settings
    target_lags='auto', 
    target_rolling_window_size='auto',
    feature_lags='auto'
)

# forecasting specific settings
# Auto configure lags and rolling window features
forecasting:
    target_lags: auto
    target_rolling_window_size: auto
    feature_lags: auto
    # other settings

Short series handling

Automated ML considers a time series a short series if there aren't enough data points to conduct the train and validation phases of model development. For more information, see training data length requirements.

AutoML has several actions it can take for short series. These actions are configurable with the short_series_handling_config setting. The default value is auto. The following table describes the settings:

Setting	Description
`auto`	The default value for short series handling. - If all series are short, pad the data. - If not all series are short, drop the short series.
`pad`	If `short_series_handling_config = pad`, automated ML adds random values to each short series found. The following lists the column types and what they're padded with: - Object columns with NaNs - Numeric columns with 0 - Boolean/logic columns with False - The target column is padded with white noise.
`drop`	If `short_series_handling_config = drop`, automated ML drops the short series, and it isn't used for training or prediction. Predictions for these series return `NaN`.
`None`	No series is padded or dropped

In the following example, set the short series handling so that all short series are padded to the minimum length:

Python SDK
Azure CLI

forecasting_job.set_forecast_settings(
    ...,  # other settings
    short_series_handling_config='pad'
)

# forecasting specific settings
# Auto configure lags and rolling window features
forecasting:
    short_series_handling_config: pad
    # other settings

Caution

Padding can impact the accuracy of the resulting model, since you introduce artificial data to avoid training failures. If many of the series are short, you might also see some impact in explainability results.

Frequency and target data aggregation

Use the frequency and data aggregation options to avoid failures caused by irregular data. Your data is irregular if it doesn't follow a set cadence in time, like hourly or daily. Point-of-sales data is a good example of irregular data. In these cases, AutoML can aggregate your data to a desired frequency and then build a forecasting model from the aggregates.

You need to set the frequency and target_aggregate_function settings to handle irregular data. The frequency setting accepts Pandas DateOffset strings as input. Supported values for the aggregation function are:

Function	Description
`sum`	Sum of target values
`mean`	Mean or average of target values
`min`	Minimum value of a target
`max`	Maximum value of a target

The target column values are aggregated according to the specified operation. Typically, sum is appropriate for most scenarios.
Sum, mean, minimum value, and maximum value aggregate numerical predictor columns in your data. As a result, automated ML generates new columns suffixed with the aggregation function name and applies the selected aggregate operation.
Mode aggregates the data for categorical predictor columns. It's the most prominent category in the window.
Minimum value, maximum value, and mode aggregate the data predictor columns.

The following example sets the frequency to hourly and the aggregation function to summation:

Python SDK
Azure CLI

# Aggregate the data to hourly frequency
forecasting_job.set_forecast_settings(
    ...,  # other settings
    frequency='H',
    target_aggregate_function='sum'
)

# forecasting specific settings
# Auto configure lags and rolling window features
forecasting:
    frequency: H
    target_aggregate_function: sum
    # other settings

Custom cross-validation settings

There are two customizable settings that control cross-validation for forecasting jobs: the number of folds, n_cross_validations, and the step size defining the time offset between folds, cv_step_size. For more information on the meaning of these parameters, see forecasting model selection.

By default, AutoML sets both settings automatically based on characteristics of your data. Advanced users might want to set them manually. For example, suppose you have daily sales data and you want your validation setup to consist of five folds with a seven-day offset between adjacent folds. The following code sample shows how to set these values:

Python SDK
Azure CLI

from azure.ai.ml import automl

# Create a job with five CV folds
forecasting_job = automl.forecasting(
    ...,  # other training parameters
    n_cross_validations=5,
)

# Set the step size between folds to seven days
forecasting_job.set_forecast_settings(
    ...,  # other settings
    cv_step_size=7
)

$schema: https://azuremlsdk2.blob.core.chinacloudapi.cn/preview/0.0.1/autoMLJob.schema.json
type: automl

experiment_name: cli-v2-automl-forecasting-job
description: A time series forecasting AutoML job
task: forecasting

training_data:
    path: "./train_data"
    type: mltable

compute: azureml:cpu-compute

primary_metric: normalized_root_mean_squared_error
target_column_name: <target_column_name>
n_cross_validations: auto

# Use five CV folds
n_cross_validations: 5

# Set the step size between folds to seven days
forecasting:
    cv_step_size: 7
    # other settings

limits:
    # limit settings

training:
    # training settings

Custom featurization

By default, AutoML augments training data with engineered features to increase the accuracy of the models. For more information, see automated feature engineering. Some of the preprocessing steps can be customized using the featurization configuration of the forecasting job.

Supported customizations for forecasting are in the following table:

Customization	Description	Options
Column purpose update	Override the autodetected feature type for the specified column.	Categorical, DateTime, Numeric
Transformer parameter update	Update the parameters for the specified imputer.	`{"strategy": "constant", "fill_value": <value>}`, `{"strategy": "median"}`, `{"strategy": "ffill"}`

For example, suppose you have a retail demand scenario where the data includes prices, an on sale flag, and a product type. The following sample shows how you can set customized types and imputers for these features:

Python SDK
Azure CLI

from azure.ai.ml.automl import ColumnTransformer

# Customize imputation methods for price and is_on_sale features
# Median value imputation for price, constant value of zero for is_on_sale
transformer_params = {
    "imputer": [
        ColumnTransformer(fields=["price"], parameters={"strategy": "median"}),
        ColumnTransformer(fields=["is_on_sale"], parameters={"strategy": "constant", "fill_value": 0}),
    ],
}

# Set the featurization
# Ensure that product_type feature is interpreted as categorical
forecasting_job.set_featurization(
    mode="custom",
    transformer_params=transformer_params,
    column_name_and_types={"product_type": "Categorical"},
)

$schema: https://azuremlsdk2.blob.core.chinacloudapi.cn/preview/0.0.1/autoMLJob.schema.json
type: automl

experiment_name: cli-v2-automl-forecasting-job
description: A time series forecasting AutoML job
task: forecasting

training_data:
    path: "./train_data"
    type: mltable

compute: azureml:cpu-compute

primary_metric: normalized_root_mean_squared_error
target_column_name: <target_column_name>
n_cross_validations: auto

# Customize imputation methods for price and is_on_sale features
# Median value imputation for price, constant value of zero for is_on_sale
featurization:
    mode: custom
    column_name_and_types:
        product_type: Categorical
    transformer_params:
        imputer:
            - fields: ["price"]
            parameters:
                strategy: median
            - fields: ["is_on_sale"]
            parameters:
                strategy: constant
                fill_value: 0

forecasting:
    # forecasting specific settings

limits:
    # limit settings

training:
    # training settings

If you're using the Azure Machine Learning studio for your experiment, see how to customize featurization in the studio.

Submitting a forecasting job

After all settings are configured, you run the forecasting job as follows:

Python SDK
Azure CLI

# Submit the AutoML job
returned_job = ml_client.jobs.create_or_update(
    forecasting_job
)

print(f"Created job: {returned_job}")

# Get a URL for the job in the AML studio user interface
returned_job.services["Studio"].endpoint

In following CLI command, the job YAML configuration is in the current working directory at the path, ./automl-forecasting-job.yml. If you run the command from a different directory, you need to change the path accordingly.

run_id=$(az ml job create --file automl-forecasting-job.yml)

You can use the stored run ID to return information about the job. The --web parameter opens the Azure Machine Learning studio web UI where you can see details on the job:

az ml job show -n $run_id --web

After the job is submitted, AutoML provisions compute resources, applies featurization and other preparation steps to the input data, and begins sweeping over forecasting models. For more information, see forecasting methodology and model search.

Orchestrate training, inference, and evaluation with components and pipelines

Important

This feature is currently in public preview. This preview version is provided without a service-level agreement, and we don't recommend it for production workloads. Certain features might not be supported or might have constrained capabilities.

For more information, see Supplemental Terms of Use for Azure Previews.

Your ML workflow likely requires more than just training. Inference, or retrieving model predictions on newer data, and evaluation of model accuracy on a test set with known target values are other common tasks that you can orchestrate in Azure Machine Learning along with training jobs. To support inference and evaluation tasks, Azure Machine Learning provides components, which are self-contained pieces of code that do one step in an Azure Machine Learning pipeline.

Python SDK
Azure CLI

In the following example, retrieve component code from a client registry:

from azure.ai.ml import MLClient
from azure.identity import DefaultAzureCredential, InteractiveBrowserCredential

# Get a credential for access to the AzureML registry
try:
    credential = DefaultAzureCredential()
    # Check if we can get token successfully.
    credential.get_token("https://management.chinacloudapi.cn/.default")
except Exception as ex:
    # Fall back to InteractiveBrowserCredential in case DefaultAzureCredential fails
    credential = InteractiveBrowserCredential()

# Create a client for accessing assets in the AzureML preview registry
ml_client_registry = MLClient(
    credential=credential,
    registry_name="azureml-preview"
)

# Create a client for accessing assets in the AzureML preview registry
ml_client_metrics_registry = MLClient(
    credential=credential,
    registry_name="azureml"
)

# Get an inference component from the registry
inference_component = ml_client_registry.components.get(
    name="automl_forecasting_inference",
    label="latest"
)

# Get a component for computing evaluation metrics from the registry
compute_metrics_component = ml_client_metrics_registry.components.get(
    name="compute_metrics",
    label="latest"
)

Next, define a factory function that creates pipelines orchestrating training, inference, and metric computation. For more information, see Configure experiment.

from azure.ai.ml import automl
from azure.ai.ml.constants import AssetTypes
from azure.ai.ml.dsl import pipeline

@pipeline(description="AutoML Forecasting Pipeline")
def forecasting_train_and_evaluate_factory(
    train_data_input,
    test_data_input,
    target_column_name,
    time_column_name,
    forecast_horizon,
    primary_metric='normalized_root_mean_squared_error',
    cv_folds='auto'
):
    # Configure the training node of the pipeline
    training_node = automl.forecasting(
        training_data=train_data_input,
        target_column_name=target_column_name,
        primary_metric=primary_metric,
        n_cross_validations=cv_folds,
        outputs={"best_model": Output(type=AssetTypes.MLFLOW_MODEL)},
    )

    training_node.set_forecasting_settings(
        time_column_name=time_column_name,
        forecast_horizon=max_horizon,
        frequency=frequency,
        # other settings
        ... 
    )
    
    training_node.set_training(
        # training parameters
        ...
    )
    
    training_node.set_limits(
        # limit settings
        ...
    )

    # Configure the inference node to make rolling forecasts on the test set
    inference_node = inference_component(
        test_data=test_data_input,
        model_path=training_node.outputs.best_model,
        target_column_name=target_column_name,
        forecast_mode='rolling',
        forecast_step=1
    )

    # Configure the metrics calculation node
    compute_metrics_node = compute_metrics_component(
        task="tabular-forecasting",
        ground_truth=inference_node.outputs.inference_output_file,
        prediction=inference_node.outputs.inference_output_file,
        evaluation_config=inference_node.outputs.evaluation_config_output_file
    )

    # return a dictionary with the evaluation metrics and the raw test set forecasts
    return {
        "metrics_result": compute_metrics_node.outputs.evaluation_result,
        "rolling_fcst_result": inference_node.outputs.inference_output_file
    }

Define train and test data inputs contained in local folders: ./train_data and ./test_data.

my_train_data_input = Input(
    type=AssetTypes.MLTABLE,
    path="./train_data"
)

my_test_data_input = Input(
    type=AssetTypes.URI_FOLDER,
    path='./test_data',
)

Finally, construct the pipeline, set its default compute, and submit the job:

pipeline_job = forecasting_train_and_evaluate_factory(
    my_train_data_input,
    my_test_data_input,
    target_column_name,
    time_column_name,
    forecast_horizon
)

# set pipeline level compute
pipeline_job.settings.default_compute = compute_name

# submit the pipeline job
returned_pipeline_job = ml_client.jobs.create_or_update(
    pipeline_job,
    experiment_name=experiment_name
)
returned_pipeline_job

$schema: https://azuremlschemas.azureedge.net/latest/pipelineJob.schema.json
type: pipeline

description: AutoML Forecasting Pipeline
experiment_name: cli-v2-automl-forecasting-pipeline

# set the default compute for the pipeline steps
settings:
    default_compute: cpu-compute

# pipeline inputs
inputs:
    train_data_input:
        type: mltable
        path: "./train_data"
    test_data_input:
        type: uri_folder
        path: "./test_data"
    target_column_name: <target column name>
    time_column_name: <time column name>
    forecast_horizon: <forecast horizon>
    primary_metric: normalized_root_mean_squared_error
    cv_folds: auto

# pipeline outputs
# output the evaluation metrics and the raw test set rolling forecasts
outputs: 
    metrics_result:
        type: uri_file
        mode: upload
    rolling_fcst_result:
        type: uri_file
        mode: upload

jobs:
  # Configure the automl training node of the pipeline 
    training_node:
        type: automl
        task: forecasting
        primary_metric: ${{parent.inputs.primary_metric}}
        target_column_name: ${{parent.inputs.target_column_name}}
        training_data: ${{parent.inputs.train_data_input}}
        n_cross_validations: ${{parent.inputs.cv_folds}}
        training:
            # training settings
        forecasting:
            time_column_name: ${{parent.inputs.time_column_name}}
            forecast_horizon: ${{parent.inputs.forecast_horizon}}
            # other forecasting specific settings
        limits:
            # limit settings
        outputs:
            best_model:
                type: mlflow_model

    # Configure the inference node to make rolling forecasts on the test set
    inference_node:
        type: command
        component: azureml://registries/azureml-preview/components/automl_forecasting_inference
        inputs:
            target_column_name: ${{parent.inputs.target_column_name}}
            forecast_mode: rolling
            forecast_step: 1
            test_data: ${{parent.inputs.test_data_input}}
            model_path: ${{parent.jobs.training_node.outputs.best_model}}
        outputs:
            inference_output_file: ${{parent.outputs.rolling_fcst_result}}
            evaluation_config_output_file:
                type: uri_file

    # Configure the metrics calculation node
    compute_metrics:
        type: command
        component: azureml://registries/azureml/compute_metrics
        inputs:
            task: "tabular-forecasting"
            ground_truth: ${{parent.jobs.inference_node.outputs.inference_output_file}}
            prediction: ${{parent.jobs.inference_node.outputs.inference_output_file}}
            evaluation_config: ${{parent.jobs.inference_node.outputs.evaluation_config_output_file}}
        outputs:
            evaluation_result: ${{parent.outputs.metrics_result}}

AutoML requires training data in MLTable format for AutoML.

Launch the pipeline run using the following command. The pipeline configuration is at the path ./automl-forecasting-pipeline.yml:

run_id=$(az ml job create --file automl-forecasting-pipeline.yml -w <Workspace> -g <Resource Group> --subscription <Subscription>)

Once submitted, the pipeline runs AutoML training, rolling evaluation inference, and metric calculation in sequence. You can monitor and inspect the run in the studio UI. When the run is finished, you can download the rolling forecasts and the evaluation metrics to the local working directory:

Python SDK
Azure CLI

# Download the metrics json
ml_client.jobs.download(returned_pipeline_job.name, download_path=".", output_name='metrics_result')

# Download the rolling forecasts
ml_client.jobs.download(returned_pipeline_job.name, download_path=".", output_name='rolling_fcst_result')

az ml job download --name $run_id --download-path . --output-name metrics_result
az ml job download --name $run_id --download-path . --output-name rolling_fcst_result

You can find the metrics results in ./named-outputs/metrics_results/evaluationResult/metrics.json and the forecasts, in JSON lines format, in ./named-outputs/rolling_fcst_result/inference_output_file.

For more information on rolling evaluation, see Inference and evaluation of forecasting models.

Forecast at scale: many models

Important

For more information, see Supplemental Terms of Use for Azure Previews.

The many models components in AutoML enable you to train and manage millions of models in parallel. For more information on many models concepts, see Many models.

Many models training configuration

The many models training component accepts a YAML format configuration file of AutoML training settings. The component applies these settings to each AutoML instance it launches. This YAML file has the same specification as the Forecasting Job plus parameters partition_column_names and allow_multi_partitions.

Parameter	Description
partition_column_names	Column names in the data that, when grouped, define the data partitions. The many models training component launches an independent training job on each partition.
allow_multi_partitions	An optional flag that allows training one model per partition when each partition contains more than one unique time series. The default value is `false`.

The following sample provides a configuration template:

$schema: https://azuremlsdk2.blob.core.chinacloudapi.cn/preview/0.0.1/autoMLJob.schema.json
type: automl

description: A time series forecasting job config
compute: azureml:<cluster-name>
task: forecasting
primary_metric: normalized_root_mean_squared_error
target_column_name: sales
n_cross_validations: 3

forecasting:
  time_column_name: date
  time_series_id_column_names: ["state", "store"]
  forecast_horizon: 28

training:
  blocked_training_algorithms: ["ExtremeRandomTrees"]

limits:
  timeout_minutes: 15
  max_trials: 10
  max_concurrent_trials: 4
  max_cores_per_trial: -1
  trial_timeout_minutes: 15
  enable_early_termination: true
  
partition_column_names: ["state", "store"]
allow_multi_partitions: false

In subsequent examples, the configuration is stored at the path, ./automl_settings_mm.yml`.

Many models pipeline

Next, define a factory function that creates pipelines for orchestration of many models training, inference, and metric computation. The parameters of this factory function are detailed in the following table:

Parameter	Description
max_nodes	Number of compute nodes to use in the training job
max_concurrency_per_node	Number of AutoML processes to run on each node. Hence, the total concurrency of a many models jobs is `max_nodes * max_concurrency_per_node`.
parallel_step_timeout_in_seconds	Many models component timeout given in number of seconds.
retrain_failed_models	Flag to enable retraining for failed models. This value is useful if you did previous many models runs that resulted in failed AutoML jobs on some data partitions. When this flag is enabled, many models only launch training jobs for previously failed partitions.
forecast_mode	Inference mode for model evaluation. Valid values are `recursive` and `rolling`. For more information, see Inference and evaluation of forecasting models.
forecast_step	Step size for rolling forecast. For more information, see Inference and evaluation of forecasting models.

The following sample illustrates a factory method for constructing many models training and model evaluation pipelines:

Python SDK
Azure CLI

from azure.ai.ml import MLClient
from azure.identity import DefaultAzureCredential, InteractiveBrowserCredential

# Get a credential for access to the AzureML registry
try:
    credential = DefaultAzureCredential()
    # Check if we can get token successfully.
    credential.get_token("https://management.chinacloudapi.cn/.default")
except Exception as ex:
    # Fall back to InteractiveBrowserCredential in case DefaultAzureCredential fails
    credential = InteractiveBrowserCredential()

# Get a many models training component
mm_train_component = ml_client_registry.components.get(
    name='automl_many_models_training',
    version='latest'
)

# Get a many models inference component
mm_inference_component = ml_client_registry.components.get(
    name='automl_many_models_inference',
    version='latest'
)

# Get a component for computing evaluation metrics
compute_metrics_component = ml_client_metrics_registry.components.get(
    name="compute_metrics",
    label="latest"
)

@pipeline(description="AutoML Many Models Forecasting Pipeline")
def many_models_train_evaluate_factory(
    train_data_input,
    test_data_input,
    automl_config_input,
    compute_name,
    max_concurrency_per_node=4,
    parallel_step_timeout_in_seconds=3700,
    max_nodes=4,
    retrain_failed_model=False,
    forecast_mode="rolling",
    forecast_step=1
):
    mm_train_node = mm_train_component(
        raw_data=train_data_input,
        automl_config=automl_config_input,
        max_nodes=max_nodes,
        max_concurrency_per_node=max_concurrency_per_node,
        parallel_step_timeout_in_seconds=parallel_step_timeout_in_seconds,
        retrain_failed_model=retrain_failed_model,
        compute_name=compute_name
    )

    mm_inference_node = mm_inference_component(
        raw_data=test_data_input,
        max_nodes=max_nodes,
        max_concurrency_per_node=max_concurrency_per_node,
        parallel_step_timeout_in_seconds=parallel_step_timeout_in_seconds,
        optional_train_metadata=mm_train_node.outputs.run_output,
        forecast_mode=forecast_mode,
        forecast_step=forecast_step,
        compute_name=compute_name
    )

    compute_metrics_node = compute_metrics_component(
        task="tabular-forecasting",
        prediction=mm_inference_node.outputs.evaluation_data,
        ground_truth=mm_inference_node.outputs.evaluation_data,
        evaluation_config=mm_inference_node.outputs.evaluation_configs
    )

    # Return the metrics results from the rolling evaluation
    return {
        "metrics_result": compute_metrics_node.outputs.evaluation_result
    }

Construct the pipeline via the factory function. The training and test data are in local folders ./data/train and ./data/test, respectively. Finally, set the default compute and submit the job as in the following sample:

pipeline_job = many_models_train_evaluate_factory(
    train_data_input=Input(
        type="uri_folder",
        path="./data/train"
    ),
    test_data_input=Input(
        type="uri_folder",
        path="./data/test"
    ),
    automl_config=Input(
        type="uri_file",
        path="./automl_settings_mm.yml"
    ),
    compute_name="<cluster name>"
)
pipeline_job.settings.default_compute = "<cluster name>"

returned_pipeline_job = ml_client.jobs.create_or_update(
    pipeline_job,
    experiment_name=experiment_name,
)
ml_client.jobs.stream(returned_pipeline_job.name)

$schema: https://azuremlschemas.azureedge.net/latest/pipelineJob.schema.json
type: pipeline

description: AutoML Many Models Forecasting Pipeline
experiment_name: cli-v2-automl-mm-forecasting-pipeline

# set the default compute for the pipeline steps
settings:
    default_compute: azureml:cpu-compute

# pipeline inputs
inputs:
    train_data_input:
        type: uri_folder
        path: "./train_data"
        mode: direct
    test_data_input:
        type: uri_folder
        path: "./test_data"
    automl_config_input:
        type: uri_file
        path: "./automl_settings_mm.yml"
    max_nodes: 4
    max_concurrency_per_node: 4
    parallel_step_timeout_in_seconds: 3700
    forecast_mode: rolling
    forecast_step: 1
    retrain_failed_model: False

# pipeline outputs
# output the evaluation metrics and the raw test set rolling forecasts
outputs: 
    metrics_result:
        type: uri_file
        mode: upload

jobs:
    # Configure AutoML many models training component
    mm_train_node:
        type: command
        component: azureml://registries/azureml-preview/components/automl_many_models_training
        inputs:
            raw_data: ${{parent.inputs.train_data_input}}
            automl_config: ${{parent.inputs.automl_config_input}}
            max_nodes: ${{parent.inputs.max_nodes}}
            max_concurrency_per_node: ${{parent.inputs.max_concurrency_per_node}}
            parallel_step_timeout_in_seconds: ${{parent.inputs.parallel_step_timeout_in_seconds}}
            retrain_failed_model: ${{parent.inputs.retrain_failed_model}}
        outputs:
            run_output:
                type: uri_folder

    # Configure the inference node to make rolling forecasts on the test set
    mm_inference_node:
        type: command
        component: azureml://registries/azureml-preview/components/automl_many_models_inference
        inputs:
            raw_data: ${{parent.inputs.test_data_input}}
            max_concurrency_per_node: ${{parent.inputs.max_concurrency_per_node}}
            parallel_step_timeout_in_seconds: ${{parent.inputs.parallel_step_timeout_in_seconds}}
            forecast_mode: ${{parent.inputs.forecast_mode}}
            forecast_step: ${{parent.inputs.forecast_step}}
            max_nodes: ${{parent.inputs.max_nodes}}
            optional_train_metadata: ${{parent.jobs.mm_train_node.outputs.run_output}}
        outputs:
            run_output:
                type: uri_folder
            evaluation_configs:
                type: uri_file
            evaluation_data:
                type: uri_file

    # Configure the metrics calculation node
    compute_metrics:
        type: command
        component: azureml://registries/azureml/components/compute_metrics
        inputs:
            task: "tabular-forecasting"
            ground_truth: ${{parent.jobs.mm_inference_node.outputs.evaluation_data}}
            prediction: ${{parent.jobs.mm_inference_node.outputs.evaluation_data}}
            evaluation_config: ${{parent.jobs.mm_inference_node.outputs.evaluation_configs}}
        outputs:
            evaluation_result: ${{parent.outputs.metrics_result}}

You launch the pipeline job with the following command. The many models pipeline configuration is at the path ./automl-mm-forecasting-pipeline.yml:

az ml job create --file automl-mm-forecasting-pipeline.yml -w <Workspace> -g <Resource Group> --subscription <Subscription>

After the job finishes, the evaluation metrics can be downloaded locally using the same procedure as in the single training run pipeline.

For a more detailed example, see the demand forecasting with many models notebook for a more detailed example.

Note

The many models training and inference components conditionally partition your data according to the partition_column_names setting so that each partition is in its own file. This process can be very slow or fail when data is very large. In this case, we recommend partitioning your data manually before running many models training or inference.

Forecast at scale: hierarchical time series

Important

For more information, see Supplemental Terms of Use for Azure Previews.

The hierarchical time series (HTS) components in AutoML enable you to train a large number of models on data with hierarchical structure. For more information, see the HTS article section.

HTS training configuration

The HTS training component accepts a YAML format configuration file of AutoML training settings. The component applies these settings to each AutoML instance it launches. This YAML file has the same specification as the Forecasting Job plus other parameters related to the hierarchy information:

Parameter	Description
hierarchy_column_names	A list of column names in the data that define the hierarchical structure of the data. The order of the columns in this list determines the hierarchy levels. The degree of aggregation decreases with the list index. That is, the last column in the list defines the leaf, or most disaggregated, level of the hierarchy.
hierarchy_training_level	The hierarchy level to use for forecast model training.

The following shows a sample configuration:

$schema: https://azuremlsdk2.blob.core.chinacloudapi.cn/preview/0.0.1/autoMLJob.schema.json
type: automl

description: A time series forecasting job config
compute: azureml:cluster-name
task: forecasting
primary_metric: normalized_root_mean_squared_error
log_verbosity: info
target_column_name: sales
n_cross_validations: 3

forecasting:
  time_column_name: "date"
  time_series_id_column_names: ["state", "store", "SKU"]
  forecast_horizon: 28

training:
  blocked_training_algorithms: ["ExtremeRandomTrees"]

limits:
  timeout_minutes: 15
  max_trials: 10
  max_concurrent_trials: 4
  max_cores_per_trial: -1
  trial_timeout_minutes: 15
  enable_early_termination: true
  
hierarchy_column_names: ["state", "store", "SKU"]
hierarchy_training_level: "store"

In subsequent examples, the configuration is stored at the path, ./automl_settings_hts.yml.

HTS pipeline

Next, define a factory function that creates pipelines for orchestration of HTS training, inference, and metric computation. The parameters of this factory function are detailed in the following table:

Parameter	Description
forecast_level	The level of the hierarchy to retrieve forecasts for
allocation_method	Allocation method to use when forecasts are disaggregated. Valid values are `proportions_of_historical_average` and `average_historical_proportions`.
max_nodes	Number of compute nodes to use in the training job
max_concurrency_per_node	Number of AutoML processes to run on each node. Hence, the total concurrency of an HTS job is `max_nodes * max_concurrency_per_node`.
parallel_step_timeout_in_seconds	Many models component timeout given in number of seconds.
forecast_mode	Inference mode for model evaluation. Valid values are `recursive` and `rolling`. For more information, see the model evaluation article.
forecast_step	Step size for rolling forecast. For more information, see the model evaluation article.

Python SDK
Azure CLI

from azure.ai.ml import MLClient
from azure.identity import DefaultAzureCredential, InteractiveBrowserCredential

# Get a credential for access to the AzureML registry
try:
    credential = DefaultAzureCredential()
    # Check if we can get token successfully.
    credential.get_token("https://management.chinacloudapi.cn/.default")
except Exception as ex:
    # Fall back to InteractiveBrowserCredential in case DefaultAzureCredential fails
    credential = InteractiveBrowserCredential()

# Get a HTS training component
hts_train_component = ml_client_registry.components.get(
    name='automl_hts_training',
    version='latest'
)

# Get a HTS inference component
hts_inference_component = ml_client_registry.components.get(
    name='automl_hts_inference',
    version='latest'
)

# Get a component for computing evaluation metrics
compute_metrics_component = ml_client_metrics_registry.components.get(
    name="compute_metrics",
    label="latest"
)

@pipeline(description="AutoML HTS Forecasting Pipeline")
def hts_train_evaluate_factory(
    train_data_input,
    test_data_input,
    automl_config_input,
    max_concurrency_per_node=4,
    parallel_step_timeout_in_seconds=3700,
    max_nodes=4,
    forecast_mode="rolling",
    forecast_step=1,
    forecast_level="SKU",
    allocation_method='proportions_of_historical_average'
):
    hts_train = hts_train_component(
        raw_data=train_data_input,
        automl_config=automl_config_input,
        max_concurrency_per_node=max_concurrency_per_node,
        parallel_step_timeout_in_seconds=parallel_step_timeout_in_seconds,
        max_nodes=max_nodes
    )
    hts_inference = hts_inference_component(
        raw_data=test_data_input,
        max_nodes=max_nodes,
        max_concurrency_per_node=max_concurrency_per_node,
        parallel_step_timeout_in_seconds=parallel_step_timeout_in_seconds,
        optional_train_metadata=hts_train.outputs.run_output,
        forecast_level=forecast_level,
        allocation_method=allocation_method,
        forecast_mode=forecast_mode,
        forecast_step=forecast_step
    )
    compute_metrics_node = compute_metrics_component(
        task="tabular-forecasting",
        prediction=hts_inference.outputs.evaluation_data,
        ground_truth=hts_inference.outputs.evaluation_data,
        evaluation_config=hts_inference.outputs.evaluation_configs
    )

    # Return the metrics results from the rolling evaluation
    return {
        "metrics_result": compute_metrics_node.outputs.evaluation_result
    }

Construct the pipeline by using the factory function. The training and test data are in local folders ./data/train and ./data/test, respectively. Finally, set the default compute and submit the job as in the following sample:

pipeline_job = hts_train_evaluate_factory(
    train_data_input=Input(
        type="uri_folder",
        path="./data/train"
    ),
    test_data_input=Input(
        type="uri_folder",
        path="./data/test"
    ),
    automl_config=Input(
        type="uri_file",
        path="./automl_settings_hts.yml"
    )
)
pipeline_job.settings.default_compute = "cluster-name"

returned_pipeline_job = ml_client.jobs.create_or_update(
    pipeline_job,
    experiment_name=experiment_name,
)
ml_client.jobs.stream(returned_pipeline_job.name)

$schema: https://azuremlschemas.azureedge.net/latest/pipelineJob.schema.json
type: pipeline

description: AutoML Many Models Forecasting Pipeline
experiment_name: cli-v2-automl-mm-forecasting-pipeline

# set the default compute for the pipeline steps
settings:
    default_compute: cpu-compute

# pipeline inputs
inputs:
    train_data_input:
        type: uri_folder
        path: "./train_data"
        mode: direct
    test_data_input:
        type: uri_folder
        path: "./test_data"
    automl_config_input:
        type: uri_file
        path: "./automl_settings_hts.yml"
    max_concurrency_per_node: 4
    parallel_step_timeout_in_seconds: 3700
    max_nodes: 4
    forecast_mode: rolling
    forecast_step: 1
    allocation_method: proportions_of_historical_average
    forecast_level: # forecast level

# pipeline outputs
# output the evaluation metrics and the raw test set rolling forecasts
outputs: 
    metrics_result:
        type: uri_file
        mode: upload

jobs:
    # Configure AutoML many models training component
    hts_train_node:
        type: command
        component: azureml://registries/azureml-preview/components/automl_hts_training
        inputs:
            raw_data: ${{parent.inputs.train_data_input}}
            automl_config: ${{parent.inputs.automl_config_input}}
            max_nodes: ${{parent.inputs.max_nodes}}
            max_concurrency_per_node: ${{parent.inputs.max_concurrency_per_node}}
            parallel_step_timeout_in_seconds: ${{parent.inputs.parallel_step_timeout_in_seconds}}
        outputs:
            run_output:
                type: uri_folder


    # Configure the inference node to make rolling forecasts on the test set
    hts_inference_node:
        type: command
        component: azureml://registries/azureml-preview/components/automl_hts_inference
        inputs:
            raw_data: ${{parent.inputs.test_data_input}}
            max_concurrency_per_node: ${{parent.inputs.max_concurrency_per_node}}
            parallel_step_timeout_in_seconds: ${{parent.inputs.parallel_step_timeout_in_seconds}}
            forecast_mode: ${{parent.inputs.forecast_mode}}
            forecast_step: ${{parent.inputs.forecast_step}}
            max_nodes: ${{parent.inputs.max_nodes}}
            optional_train_metadata: ${{parent.jobs.hts_train_node.outputs.run_output}}
            forecast_level: ${{parent.inputs.forecast_level}}
            allocation_method: ${{parent.inputs.allocation_method}}
        outputs:
            run_output:
                type: uri_folder
            evaluation_configs:
                type: uri_file
            evaluation_data:
                type: uri_file

    # Configure the metrics calculation node
    compute_metrics:
        type: command
        component: azureml://registries/azureml/components/compute_metrics
        inputs:
            task: "tabular-forecasting"
            ground_truth: ${{parent.jobs.hts_inference_node.outputs.evaluation_data}}
            prediction: ${{parent.jobs.hts_inference_node.outputs.evaluation_data}}
            evaluation_config: ${{parent.jobs.hts_inference_node.outputs.evaluation_configs}}
        outputs:
            evaluation_result: ${{parent.outputs.metrics_result}}

You launch the pipeline job with the following command. The many models pipeline configuration is at the path ./automl-hts-forecasting-pipeline.yml:

az ml job create --file automl-hts-forecasting-pipeline.yml -w <Workspace> -g <Resource Group> --subscription <Subscription>

After the job finishes, the evaluation metrics can be downloaded locally using the same procedure as in the single training run pipeline.

For a more detailed example, see the demand forecasting with hierarchical time series notebook.

Note

The HTS training and inference components conditionally partition your data according to the hierarchy_column_names setting so that each partition is in its own file. This process can be very slow or fail when data is very large. In this case, we recommend partitioning your data manually before running HTS training or inference.

Forecast at scale: distributed DNN training

To learn how distributed training works for forecasting tasks, see Distributed DNN training.
To see code samples, see AutoML at scale: distributed training.

Example notebooks

For detailed code examples of advanced forecasting configuration, see the forecasting sample notebooks:

Set up AutoML to train a time-series forecasting model with SDK and CLI

Prerequisites

Training and validation data

Compute to run experiment

Configure experiment

Forecast job settings

Optional forecasting job settings

Model search settings

Enable deep learning

Lag and rolling window features

Short series handling

Frequency and target data aggregation

Custom cross-validation settings

Custom featurization

Submitting a forecasting job

Orchestrate training, inference, and evaluation with components and pipelines

Forecast at scale: many models

Many models training configuration

Many models pipeline

Forecast at scale: hierarchical time series

HTS training configuration

HTS pipeline

Forecast at scale: distributed DNN training

Example notebooks

Related content

Additional resources