Smile is a fast and comprehensive machine learning engine.


With advanced data structures and algorithms, Smile delivers the state-of-art performance.

Compared to this third-party benchmark, Smile outperforms R, Python, Spark, H2O, xgboost significantly. Smile is a couple of times faster than the closest competitor. The memory usage is also very efficient. If we can train advanced machine learning models on a PC, why buy a cluster?

Training Time (seconds)

Ease of Use

Write applications quickly in Java, Scala, or any JVM languages. Data scientists and developers can speak the same language now!

Smile provides hundreds advanced algorithms with clean interface. Scala API also offers high-level operators that make it easy to build machine learning apps. And you can use it interactively from the shell, embedded in Scala.

var iris = Read.arff("iris.arff");

var model ="class"), iris);

DataFrame, Model Fitting, and Metrics

val iris = read.arff("iris.arff")

val model = randomForest("class" ~, iris)


DataFrame, Model Fitting, and Metrics

val iris = read.arff("iris.arff")

val model = randomForest(Formula.lhs("class"), iris)

DataFrame, Model Fitting, and Metrics

(let [iris (read-arff
      model (random-forest
             (Formula/lhs "class") iris)]
  (.metrics model))

DataFrame, Model Fitting, and Metrics

var iris = Read.arff("iris.arff")

var model ="class"), iris)

println model.metrics()
DataFrame, Model Fitting, and Metrics


The most complete machine learning engine. Smile covers every aspect of machine learning.

Classification, regression, clustering, association rule mining, feature selection, manifold learning, multidimensional scaling, genetic algorithm, missing value imputation, efficient nearest neighbor search, etc. See the sidebar for a list of available algorithms.

Natural Language Processing

Understanding human language, and the intent behind our words.

Tokenizers, stemming, word2vec, phrase detection, part-of-speech tagging, keyword extraction, named entity recognition, sentiment analysis, relevance ranking, taxomony.

Mathematics and Statistics

Hidden gems in Smile.

From special functions, linear algebra, to random number generators, statistical distributions and hypothesis tests, Smile provides an advanced numerical computing environment. In additions, graph, wavlets, and a variety of interpolation algorithms are implemented. Smile even includes a computer algerbra system.

var A = Matrix.randn(3, 3);
double[] x = {1.0, 2.0, 3.0};
var lu =;
Linear Algebra

int[] bins1 = {8, 13, 16, 10, 3};

int[] bins2 = {4,  9, 14, 16, 7};

Hypothesis.chisq.test(bins1, bins2);

val x = Var("x")
val y = Var("y")
val e = x**2 + y**3 + x**2 * cot(y**3)
val dx = e.d(x)
Computer Algebra System

Data Visualization

Interactive 2D/3D math plot.

Scatter plot, line plot, staircase plot, bar plot, box plot, heatmap, hexmap, histogram, qq plot, surface, grid, contour, dendrogram, sparse matrix visualization, wireframe, etc. Smile also supports declarative data visualization that compiles to Vega-Lite.

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