BigML Node.js Bindings

BigML makes machine learning easy by taking care of the details required to add data-driven decisions and predictive power to your company. Unlike other machine learning services, BigML creates beautiful predictive models that can be easily understood and interacted with.

These BigML Node.js bindings allow you to interact with BigML.io, the API for BigML. You can use it to easily create, retrieve, list, update, and delete BigML resources (i.e., sources, datasets, models and predictions).

This module is licensed under the Apache License, Version 2.0.

Support

Please report problems and bugs to our BigML.io issue tracker.

Discussions about the different bindings take place in the general BigML mailing list. Or join us in our Campfire chatroom.

Requirements

Node 0.10 and later are currently supported by these bindings.

The mandatory third-party dependencies are the request, winston, form-data, mersenne-twister, snowball, combined-stream, mime, async, jStat and fast-csv libraries.

The testing environment requires the additional mocha package that can be installed with the following command:

$ sudo npm install -g mocha

Installation

To install the latest stable release with npm:

$ npm install bigml

You can also install the development version of the bindings by cloning the Git repository to your local computer and issuing:

$ npm install .

Testing

The test suite is run automatically using mocha as test framework. As all the tested api objects perform one or more connections to the remote resources in bigml.com, you may have to enlarge the default timeout used by mocha in each test. For instance:

$ mocha -t 20000

will set the timeout limit to 20 seconds. This limit should typically be enough, but you can change it to fit the latencies of your connection.

Importing the modules

To use the library, import it with require:

$ node
> bigml = require('bigml');

this will give you access to the following library structure:

- bigml.constants                   common constants
- bigml.BigML                       connection object
- bigml.Resource                    common API methods
- bigml.Source                      Source API methods
- bigml.Dataset                     Dataset API methods
- bigml.Model                       Model API methods
- bigml.Ensemble                    Ensemble API methods
- bigml.Prediction                  Prediction API methods
- bigml.BatchPrediction             BatchPrediction API methods
- bigml.Evaluation                  Evaluation API methods
- bigml.Cluster                     Cluster API methods
- bigml.Centroid                    Centroid API methods
- bigml.BatchCentroid               BatchCentroid API methods
- bigml.Anomaly                     Anomaly detector API methods
- bigml.AnomalyScore                Anomaly score API methods
- bigml.BatchAnomalyScore           BatchAnomalyScore API methods
- bigml.Project                     Project API methods
- bigml.Sample                      Sample API methods
- bigml.Correlation                 Correlation API methods
- bigml.StatisticalTests            StatisticalTest API methods
- bigml.LogisticRegression          LogisticRegression API methods
- bigml.Association                 Association API methods
- bigml.AssociationSet              Associationset API methods
- bigml.TopicModel                  Topic Model API methods
- bigml.TopicDistribution           Topic Distribution API methods
- bigml.BatchTopicDistribution      Batch Topic Distribution API methods
- bigml.Deepnet                     Deepnet API methods
- bigml.Fusion                      Fusion API methods
- bigml.PCA                         PCA API methods
- bigml.Projection                  Projection API methods
- bigml.BatchProjection             Batch Projection API methods
- bigml.LinearRegression            Linear Regression API methods
- bigml.Script                      Script API methods
- bigml.Execution                   Execution API methods
- bigml.Library                     Library API methods
- bigml.LocalModel                  Model for local predictions
- bigml.LocalEnsemble               Ensemble for local predictions
- bigml.LocalCluster                Cluster for local centroids
- bigml.LocalAnomaly                Anomaly detector for local anomaly scores
- bigml.LocalLogisticRegression     Logistic regression model for local predictions
- bigml.LocalAssociation            Association model for associaton rules
- bigml.LocalTopicModel             Topic Model for local predictions
- bigml.LocalTimeSeries             Time Series for local forecasts
- bigml.LocalDeepnet                Deepnets for local predictions
- bigml.LocalFusion                 Fusions for local predictions
- bigml.LocalPCA                    PCA for local projections
- bigml.LocalLinearRegression       Linear Regression for local predictions

Authentication

All the requests to BigML.io must be authenticated using your username and API key and are always transmitted over HTTPS.

This module will look for your username and API key in the environment variables BIGML_USERNAME and BIGML_API_KEY respectively. You can add the following lines to your .bashrc or .bash_profile to set those variables automatically when you log in::

export BIGML_USERNAME=myusername
export BIGML_API_KEY=ae579e7e53fb9abd646a6ff8aa99d4afe83ac291

With that environment set up, connecting to BigML is a breeze::

connection = new bigml.BigML();

Otherwise, you can initialize directly when instantiating the BigML class as follows::

connection = new bigml.BigML('myusername',
                             'ae579e7e53fb9abd646a6ff8aa99d4afe83ac291')

Quick Start

Let's see the steps that will lead you from this csv file containing the Iris flower dataset to predicting the species of a flower whose sepal length is 5 and whose sepal width is 2.5. By default, BigML considers the last field (species) in the row as the objective field (i.e., the field that you want to generate predictions for). The csv structure is::

sepal length,sepal width,petal length,petal width,species
5.1,3.5,1.4,0.2,Iris-setosa
4.9,3.0,1.4,0.2,Iris-setosa
4.7,3.2,1.3,0.2,Iris-setosa
...

The steps required to generate a prediction are creating a set of source, dataset and model objects::

    var bigml = require('bigml');
    var source = new bigml.Source();
    source.create('./data/iris.csv', function(error, sourceInfo) {
      if (!error && sourceInfo) {
        var dataset = new bigml.Dataset();
        dataset.create(sourceInfo, function(error, datasetInfo) {
          if (!error && datasetInfo) {
            var model = new bigml.Model();
            model.create(datasetInfo, function (error, modelInfo) {
              if (!error && modelInfo) {
                var prediction = new bigml.Prediction();
                prediction.create(modelInfo, {'petal length': 1})
              }
            });
          }
        });
      }
    });

Note that in our example the prediction.create call has no associated callback. All the CRUD methods of any resource allow assigning a callback as the last parameter, but if you don't the default action will be printing the resulting resource or the error. For the create method:

> result:
{ code: 201,
  object:
   { category: 0,
     code: 201,
     content_type: 'text/csv',
     created: '2013-06-08T15:22:36.834797',
     credits: 0,
     description: '',
     fields_meta: { count: 0, limit: 1000, offset: 0, total: 0 },
     file_name: 'iris.csv',
     md5: 'd1175c032e1042bec7f974c91e4a65ae',
     name: 'iris.csv',
     number_of_datasets: 0,
     number_of_ensembles: 0,
     number_of_models: 0,
     number_of_predictions: 0,
     private: true,
     resource: 'source/51b34c3c37203f4678000020',
     size: 4608,
     source_parser: {},
     status:
      { code: 1,
        message: 'The request has been queued and will be processed soon' },
     subscription: false,
     tags: [],
     type: 0,
     updated: '2013-06-08T15:22:36.834844' },
  resource: 'source/51b34c3c37203f4678000020',
  location: 'https://localhost:1026/andromeda/source/51b34c3c37203f4678000020',
  error: null }

The generated objects can be retrieved, updated and deleted through the corresponding REST methods. For instance, in the previous example you would use:

    bigml = require('bigml');
    var source = new bigml.Source();
    source.get('source/51b25fb237203f4410000010', function (error, resource) {
        if (!error && resource) {
          console.log(resource);
        }
      })

to recover and show the source information.

You can also generate local predictions using the information of your models::

    bigml = require('bigml');
    var localModel = new bigml.LocalModel('model/51922d0b37203f2a8c000010');
    localModel.predict({'petal length': 1},
                       function(error, prediction) {console.log(prediction)});

And similarly, for your ensembles

    bigml = require('bigml');
    var localEnsemble = new bigml.LocalEnsemble('ensemble/51901f4337203f3a9a000215');
    localEnsemble.predict({'petal length': 1}, 0,
                          function(error, prediction) {console.log(prediction)});

will generate a prediction by combining the predictions of each of the models they enclose. The example uses the plurality combination method (whose code is 0. Check the docs for more information about the available combination methods).

Additional Information

We've just drawn a first sketch. For additional information, see the files included in the docs folder.

How to Contribute

Please follow these steps:

1. Fork the project on github.com.
2. Create a new branch.
3. Commit changes to the new branch.
4. Send a pull request.

For details on the underlying API, see the BigML API documentation.