mlpack changelog

🔗 mlpack 4.5.1

2024-12-02

Fix compilation with clang 19 (#3799).
Deprecate version of data::Split() that returns a std::tuple for consistency; use other overloads instead (#3803).
Fix LSTM layer copy/move constructors (#3809).
Fix compilation if only including mlpack/methods/kde/kde_model.hpp (#3800).
Fix serialization and MinDistance() bugs with HollowBallBound (#3808).

🔗 mlpack 4.5.0

2024-09-17

Distribute STB headers as part of R package (#3724, #3726).
Added OpenMP parallelization to Hamerly, Naive, and Elkan k-means (#3761, #3762, #3764).
Added OpenMP support for fast approximation (#3685).
Implemented the Find and Fill algorithm into the Dropout Layer and added OpenMP support (#3684).
Update Python bindings to support NumPy 2.x (#3752).
Bump minimum Armadillo version to 10.8 (#3760).
Adapt NearestInterpolation ANN layer to new Layer Inteface (#3768).
Add support for arbitrary matrix types to Radical and deprecate Radical::DoRadical() in favor of Radical::Apply() (#3787).

🔗 mlpack 4.4.0

2024-05-26

Add print_training_accuracy option to LogisticRegression bindings (#3552).
Fix preprocess_split() call in documentation for LinearRegression and AdaBoost Python classes (#3563).
Added Repeat ANN layer type (#3565).
Remove round() implementation for old MSVC compilers (#3570).
(R) Added inline plugin to the R bindings to allow for other R packages to link to headers (#3626, h/t @cgiachalis).
(R) Removed extra gcc-specific options from Makevars.win (#3627, h/t @kalibera).
(R) Changed roxygen package-level documentation from using @docType package to "_PACKAGE". (#3636)
Fix floating-point accuracy issue for decision trees that sometimes caused crashes (#3595).
Use templates metaprog to distinguish between a matrix and a cube type (#3602), (#3585).
Use MatType instead of arma::Mat<eT>, (#3567), (#3607), (#3608), (#3609), (#3568).
Generalize matrix operations for armadillo and bandicoot, (#3619), (#3617), (#3610), (#3643), (#3600), (#3605), (#3629).
Change arma::conv_to to ConvTo using a local shim for bandicoot support (#3614).
Fix a bug for the stddev and mean in RandNormal() #(3651).
Allow PCA to take different matrix types (#3677).
Fix usage of precompiled headers; remove cotire (#3635).
Fix non-working verbose option for R bindings (#3691), and add global mlpack.verbose option (#3706).
Fix divide-by-zero edge case for LARS (#3701).
Templatize SparseCoding and LocalCoordinateCoding to allow different matrix types (#3709, #3711).
Fix handling of unused atoms in LocalCoordinateCoding (#3711).
Move minimum required C++ version from C++14 to C++17 (#3704).

🔗 mlpack 4.3.0

2023-11-27

Fix include ordering issue for LinearRegression (#3541).
Fix L1 regularization in case where weight is zero (#3545).
Use HTTPS for all auto-downloaded dependencies (#3550).
More robust detection of C++17 mode in the MSVC “compiler” (#3555, #3557).
Fix setting number of classes correctly in SoftmaxRegression::Train() (#3553).
Adapt MultiheadAttention and LayerNorm ANN layers to new Layer interface (#3547).
Fix inconsistent use of the “input” parameter to the Backward method in ANNs (#3551).
Allow passing weak learner hyperparameters directly to AdaBoost (#3560).

🔗 mlpack 4.2.1

2023-09-05

Reinforcement Learning: Gaussian noise (#3515).
Reinforcement Learning: Twin Delayed Deep Deterministic Policy Gradient (#3512).
Reinforcement Learning: Ornstein-Uhlenbeck noise (#3499).
Reinforcement Learning: Deep Deterministic Policy Gradient (#3494).
Add ClassProbabilities() member to DecisionTree so that the internal details of trees can be more easily inspected (#3511).
Bipolar sigmoid activation function added and invertible functions fixed (#3506).
Add auto-configured mlpack/config.hpp to contain configuration details of mlpack that are required at compile time. STB detection is now done in this file with the MLPACK_HAS_STB macro (#3519).
Fix CRAN package alias for R bindings (#3543).

🔗 mlpack 4.2.0

2023-06-14

Adapt C_ReLU, ReLU6, FlexibleReLU layers for the new neural network API (#3445).
Fix PReLU, add integration test to it (#3473).
Fix bug in LogSoftMax derivative (#3469).
Add serialize method to GaussianInitialization, LecunNormalInitialization, KathirvalavakumarSubavathiInitialization, NguyenWidrowInitialization, and OrthogonalInitialization (#3483).
Allow categorical features to preprocess_one_hot_encode (#3487).
Install mlpack and cereal headers as part of R package (#3488).
Add intercept and normalization support to LARS (#3493).
Allow adding two features simultaneously to LARS models (#3493).
Adapt FTSwish activation function (#3485).
Adapt Hyper-Sinh activation function (#3491).

🔗 mlpack 4.1.0

2023-04-26

Adapt HardTanH layer (#3454).
Adapt Softmin layer for new neural network API (#3437).
Adapt PReLU layer for new neural network API (#3420).
Add CF decomposition methods: QUIC_SVDPolicy and BlockKrylovSVDPolicy (#3413, #3404).
Update outdated code in tutorials (#3398, #3401).
Bugfix for non-square convolution kernels (#3376).
Fix a few missing includes in <mlpack.hpp> (#3374).
Fix DBSCAN handling of non-core points (#3346).
Avoid deprecation warnings in Armadillo 11.4.4+ (#3405).
Issue runtime error when serialization of neural networks is attempted but MLPACK_ENABLE_ANN_SERIALIZATION is not defined (#3451).

🔗 mlpack 4.0.1

2022-12-23

Fix mapping of categorical data for Julia bindings (#3305).
Bugfix: catch all exceptions when running bindings from Julia, instead of crashing (#3304).
Various Python configuration fixes for Windows and OS X (#3312, #3313, #3311, #3309, #3308, #3297, #3302).
Optimize and strip compiled Python bindings when possible, resulting in significant size minimization (#3310).
The /std:c++17 and /Zc:__cplusplus options are now required when using Visual Studio (#3318). Documentation and compile-time checks added.
Set BUILD_TESTS to OFF by default. If you want to build tests, like mlpack_test, manually set BUILD_TESTS to ON in your CMake configuration step (#3316).
Fix handling of transposed matrix parameters in Python, Julia, R, and Go bindings (#3327).
Comment out definition of ARMA_NO DEBUG. This allows various Armadillo run-time checks such as non-conforming matrices and out-of-bounds element access. In turn this helps tracking down bugs and incorrect usage (#3322).

🔗 mlpack 4.0.0

2022-10-23

Bump C++ standard requirement to C++14 (#3233).
Fix Perceptron to work with cross-validation framework (#3190).
Migrate from boost tests to Catch2 framework (#2523), (#2584).
Bump minimum armadillo version from 8.400 to 9.800 (#3043), (#3048).
Adding a copy constructor in the Convolution layer (#3067).
Replace boost::spirit parser by a local efficient implementation (#2942).
Disable correctly the autodownloader + fix tests stability (#3076).
Replace boost::any with core::v2::any or std::any if available (#3006).
Remove old non used Boost headers (#3005).
Replace boost::enable_if with std::enable_if (#2998).
Replace boost::is_same with std::is_same (#2993).
Remove invalid option for emsmallen and STB (#2960).
Check for armadillo dependencies before downloading armadillo (#2954).
Disable the usage of autodownloader by default (#2953).
Install dependencies downloaded with the autodownloader (#2952).
Download older Boost if the compiler is old (#2940).
Add support for embedded systems (#2531).
Build mlpack executable statically if the library is statically linked (#2931).
Fix cover tree loop bug on embedded arm systems (#2869).
Fix a LAPACK bug in FindArmadillo.cmake (#2929).
Add an autodownloader to get mlpack dependencies (#2927).
Remove Coverage files and configurations from CMakeLists (#2866).
Added Multi Label Soft Margin Loss loss function for neural networks (#2345).
Added Decision Tree Regressor (#2905). It can be used using the class mlpack::tree::DecisionTreeRegressor. It is accessible only though C++.
Added dict-style inspection of mlpack models in python bindings (#2868).
Added Extra Trees Algorithm (#2883). Currently, it can be used using the class mlpack::tree::ExtraTrees, but only through C++.
Add Flatten T Swish activation function (flatten-t-swish.hpp)
Added warm start feature to Random Forest (#2881); this feature is accessible from mlpack’s bindings to different languages.
Added Pixel Shuffle layer (#2563).
Add “check_input_matrices” option to python bindings that checks for NaN and inf values in all the input matrices (#2787).
Add Adjusted R squared functionality to R2Score::Evaluate (#2624).
Disabled all the bindings by default in CMake (#2782).
Added an implementation to Stratify Data (#2671).
Add BUILD_DOCS CMake option to control whether Doxygen documentation is built (default ON) (#2730).
Add Triplet Margin Loss function (#2762).
Add finalizers to Julia binding model types to fix memory handling (#2756).
HMM: add functions to calculate likelihood for data stream with/without pre-calculated emission probability (#2142).
Replace Boost serialization library with Cereal (#2458).
Add PYTHON_INSTALL_PREFIX CMake option to specify installation root for Python bindings (#2797).
Removed boost::visitor from model classes for knn, kfn, cf, range_search, krann, and kde bindings (#2803).
Add k-means++ initialization strategy (#2813).
NegativeLogLikelihood<> now expects classes in the range 0 to numClasses - 1 (#2534).
Add Lambda1(), Lambda2(), UseCholesky(), and Tolerance() members to LARS so parameters for training can be modified (#2861).
Remove unused ElemType template parameter from DecisionTree and RandomForest (#2874).
Fix Python binding build when the CMake variable USE_OPENMP is set to OFF (#2884).
The mlpack_test target is no longer built as part of make all. Use make mlpack_test to build the tests.
Fixes to HoeffdingTree: ensure that training still works when empty constructor is used (#2964).
Fix Julia model serialization bug (#2970).
Fix LoadCSV() to use pre-populated DatasetInfo objects (#2980).
Add probabilities option to softmax regression binding, to get class probabilities for test points (#3001).
Fix thread safety issues in mlpack bindings to other languages (#2995).
Fix double-free of model pointers in R bindings (#3034).
Fix Julia, Python, R, and Go handling of categorical data for decision_tree() and hoeffding_tree() (#2971).
Depend on pkgbuild for R bindings (#3081).
Replaced Numpy deprecated code in Python bindings (#3126).

🔗 mlpack 3.4.2

2020-10-26

Added Mean Absolute Percentage Error.
Added Softmin activation function as layer in ann/layer.
Fix spurious ARMA_64BIT_WORD compilation warnings on 32-bit systems (#2665).

🔗 mlpack 3.4.1

2020-09-07

Fix incorrect parsing of required matrix/model parameters for command-line bindings (#2600).
Add manual type specification support to data::Load() and data::Save() (#2084, #2135, #2602).
Remove use of internal Armadillo functionality (#2596, #2601, #2602).

🔗 mlpack 3.4.0

2020-09-01

Issue warnings when metrics produce NaNs in KFoldCV (#2595).
Added bindings for R during Google Summer of Code (#2556).
Added common striptype function for all bindings (#2556).
Refactored common utility function of bindings to bindings/util (#2556).
Renamed InformationGain to HoeffdingInformationGain in methods/hoeffding_trees/information_gain.hpp (#2556).
Added macro for changing stream of printing and warnings/errors (#2556).
Added Spatial Dropout layer (#2564).
Force CMake to show error when it didn’t find Python/modules (#2568).
Refactor ProgramInfo() to separate out all the different information (#2558).
Add bindings for one-hot encoding (#2325).
Added Soft Actor-Critic to RL methods (#2487).
Added Categorical DQN to q_networks (#2454).
Added N-step DQN to q_networks (#2461).
Add Silhoutte Score metric and Pairwise Distances (#2406).
Add Go bindings for some missed models (#2460).
Replace boost program_options dependency with CLI11 (#2459).
Additional functionality for the ARFF loader (#2486); use case sensitive categories (#2516).
Add bayesian_linear_regression binding for the command-line, Python, Julia, and Go. Also called “Bayesian Ridge”, this is equivalent to a version of linear regression where the regularization parameter is automatically tuned (#2030).
Fix defeatist search for spill tree traversals (#2566, #1269).
Fix incremental training of logistic regression models (#2560).
Change default configuration of BUILD_PYTHON_BINDINGS to OFF (#2575).

🔗 mlpack 3.3.2

2020-06-18

Added Noisy DQN to q_networks (#2446).
Add Go bindings (#1884).
Added Dueling DQN to q_networks, Noisy linear layer to ann/layer and Empty loss to ann/loss_functions (#2414).
Storing and adding accessor method for action in q_learning (#2413).
Added accessor methods for ANN layers (#2321).
Addition of Elliot activation function (#2268).
Add adaptive max pooling and adaptive mean pooling layers (#2195).
Add parameter to avoid shuffling of data in preprocess_split (#2293).
Add MatType parameter to LSHSearch, allowing sparse matrices to be used for search (#2395).
Documentation fixes to resolve Doxygen warnings and issues (#2400).
Add Load and Save of Sparse Matrix (#2344).
Add Intersection over Union (IoU) metric for bounding boxes (#2402).
Add Non Maximal Supression (NMS) metric for bounding boxes (#2410).
Fix no_intercept and probability computation for linear SVM bindings (#2419).
Fix incorrect neighbors for k > 1 searches in approx_kfn binding, for the QDAFN algorithm (#2448).
Fix serialization of kernels with state for FastMKS (#2452).
Add RBF layer in ann module to make RBFN architecture (#2261).

🔗 mlpack 3.3.1

2020-04-29

Minor Julia and Python documentation fixes (#2373).
Updated terminal state and fixed bugs for Pendulum environment (#2354, #2369).
Added EliSH activation function (#2323).
Add L1 Loss function (#2203).
Pass CMAKE_CXX_FLAGS (compilation options) correctly to Python build (#2367).
Expose ensmallen Callbacks for sparseautoencoder (#2198).
Bugfix for LARS class causing invalid read (#2374).
Add serialization support from Julia; use mlpack.serialize() and mlpack.deserialize() to save and load from IOBuffers.

🔗 mlpack 3.3.0

2020-04-07

Added Normal Distribution to ann/dists (#2382).
Templated return type of Forward function of loss functions (#2339).
Added R2 Score regression metric (#2323).
Added poisson negative log likelihood loss function (#2196).
Added huber loss function (#2199).
Added mean squared logarithmic error loss function for neural networks (#2210).
Added mean bias loss function for neural networks (#2210).
The DecisionStump class has been marked deprecated; use the DecisionTree class with NoRecursion=true or use ID3DecisionStump instead (#2099).
Added probabilities_file parameter to get the probabilities matrix of AdaBoost classifier (#2050).
Fix STB header search paths (#2104).
Add DISABLE_DOWNLOADS CMake configuration option (#2104).
Add padding layer in TransposedConvolutionLayer (#2082).
Fix pkgconfig generation on non-Linux systems (#2101).
Use log-space to represent HMM initial state and transition probabilities (#2081).
Add functions to access parameters of Convolution and AtrousConvolution layers (#1985).
Add Compute Error function in lars regression and changing Train function to return computed error (#2139).
Add Julia bindings (#1949). Build settings can be controlled with the BUILD_JULIA_BINDINGS=(ON/OFF) and JULIA_EXECUTABLE=/path/to/julia CMake parameters.
CMake fix for finding STB include directory (#2145).
Add bindings for loading and saving images (#2019); mlpack_image_converter from the command-line, mlpack.image_converter() from Python.
Add normalization support for CF binding (#2136).
Add Mish activation function (#2158).
Update init_rules in AMF to allow users to merge two initialization rules (#2151).
Add GELU activation function (#2183).
Better error handling of eigendecompositions and Cholesky decompositions (#2088, #1840).
Add LiSHT activation function (#2182).
Add Valid and Same Padding for Transposed Convolution layer (#2163).
Add CELU activation function (#2191)
Add Log-Hyperbolic-Cosine Loss function (#2207).
Change neural network types to avoid unnecessary use of rvalue references (#2259).
Bump minimum Boost version to 1.58 (#2305).
Refactor STB support so HAS_STB macro is not needed when compiling against mlpack (#2312).
Add Hard Shrink Activation Function (#2186).
Add Soft Shrink Activation Function (#2174).
Add Hinge Embedding Loss Function (#2229).
Add Cosine Embedding Loss Function (#2209).
Add Margin Ranking Loss Function (#2264).
Bugfix for incorrect parameter vector sizes in logistic regression and softmax regression (#2359).

🔗 mlpack 3.2.2

2019-11-26

Add valid and same padding option in Convolution and Atrous Convolution layer (#1988).
Add Model() to the FFN class to access individual layers (#2043).
Update documentation for pip and conda installation packages (#2044).
Add bindings for linear SVM (#1935); mlpack_linear_svm from the command-line, linear_svm() from Python.
Add support to return the layer name as std::string (#1987).
Speed and memory improvements for the Transposed Convolution layer (#1493).
Fix Windows Python build configuration (#1885).
Validate md5 of STB library after download (#2087).
Add __version__ to __init__.py (#2092).
Correctly handle RNN sequences that are shorter than the value of rho (#2102).

🔗 mlpack 3.2.1

2019-10-01

Enforce CMake version check for ensmallen (#2032).
Fix CMake check for Armadillo version (#2029).
Better handling of when STB is not installed (#2033).
Fix Naive Bayes classifier computations in high dimensions (#2022).

🔗 mlpack 3.2.0

2019-09-25

Fix some potential infinity errors in Naive Bayes Classifier (#2022).
Fix occasionally-failing RADICAL test (#1924).
Fix gcc 9 OpenMP compilation issue (#1970).
Added support for loading and saving of images (#1903).
Add Multiple Pole Balancing Environment (#1901, #1951).
Added functionality for scaling of data (#1876); see the command-line binding mlpack_preprocess_scale or Python binding preprocess_scale().
Add new parameter maximum_depth to decision tree and random forest bindings (#1916).
Fix prediction output of softmax regression when test set accuracy is calculated (#1922).
Pendulum environment now checks for termination. All RL environments now have an option to terminate after a set number of time steps (no limit by default) (#1941).
Add support for probabilistic KDE (kernel density estimation) error bounds when using the Gaussian kernel (#1934).
Fix negative distances for cover tree computation (#1979).
Fix cover tree building when all pairwise distances are 0 (#1986).
Improve KDE pruning by reclaiming not used error tolerance (#1954, #1984).
Optimizations for sparse matrix accesses in z-score normalization for CF (#1989).
Add kmeans_max_iterations option to GMM training binding gmm_train_main.
Bump minimum Armadillo version to 8.400.0 due to ensmallen dependency requirement (#2015).

🔗 mlpack 3.1.1

2019-05-26

Fix random forest bug for numerical-only data (#1887).
Significant speedups for random forest (#1887).
Random forest now has minimum_gain_split and subspace_dim parameters (#1887).
Decision tree parameter print_training_error deprecated in favor of print_training_accuracy.
output option changed to predictions for adaboost and perceptron binding. Old options are now deprecated and will be preserved until mlpack 4.0.0 (#1882).
Concatenated ReLU layer (#1843).
Accelerate NormalizeLabels function using hashing instead of linear search (see src/mlpack/core/data/normalize_labels_impl.hpp) (#1780).
Add ConfusionMatrix() function for checking performance of classifiers (#1798).
Install ensmallen headers when it is downloaded during build (#1900).

🔗 mlpack 3.1.0

2019-04-25

Add DiagonalGaussianDistribution and DiagonalGMM classes to speed up the diagonal covariance computation and deprecate DiagonalConstraint (#1666).
Add kernel density estimation (KDE) implementation with bindings to other languages (#1301).
Where relevant, all models with a Train() method now return a double value representing the goodness of fit (i.e. final objective value, error, etc.) (#1678).
Add implementation for linear support vector machine (see src/mlpack/methods/linear_svm).
Change DBSCAN to use PointSelectionPolicy and add OrderedPointSelection (#1625).
Residual block support (#1594).
Bidirectional RNN (#1626).
Dice loss layer (#1674, #1714) and hard sigmoid layer (#1776).
output option changed to predictions and output_probabilities to probabilities for Naive Bayes binding (mlpack_nbc/nbc()). Old options are now deprecated and will be preserved until mlpack 4.0.0 (#1616).
Add support for Diagonal GMMs to HMM code (#1658, #1666). This can provide large speedup when a diagonal GMM is acceptable as an emission probability distribution.
Python binding improvements: check parameter type (#1717), avoid copying Pandas dataframes (#1711), handle Pandas Series objects (#1700).

🔗 mlpack 3.0.4

2018-11-13

Bump minimum CMake version to 3.3.2.
CMake fixes for Ninja generator by Marc Espie.

🔗 mlpack 3.0.3

2018-07-27

Fix Visual Studio compilation issue (#1443).
Allow running local_coordinate_coding binding with no initial_dictionary parameter when input_model is not specified (#1457).
Make use of OpenMP optional via the CMake ‘USE_OPENMP’ configuration variable (#1474).
Accelerate FNN training by 20-30% by avoiding redundant calculations (#1467).
Fix math::RandomSeed() usage in tests (#1462, #1440).
Generate better Python setup.py with documentation (#1460).

🔗 mlpack 3.0.2

2018-06-08

Documentation generation fixes for Python bindings (#1421).
Fix build error for man pages if command-line bindings are not being built (#1424).
Add ‘shuffle’ parameter and Shuffle() method to KFoldCV (#1412). This will shuffle the data when the object is constructed, or when Shuffle() is called.
Added neural network layers: AtrousConvolution (#1390), Embedding (#1401), and LayerNorm (layer normalization) (#1389).
Add Pendulum environment for reinforcement learning (#1388) and update Mountain Car environment (#1394).

🔗 mlpack 3.0.1

2018-05-10

Fix intermittently failing tests (#1387).
Add big-batch SGD (BBSGD) optimizer in src/mlpack/core/optimizers/bigbatch_sgd/ (#1131).
Fix simple compiler warnings (#1380, #1373).
Simplify NeighborSearch constructor and Train() overloads (#1378).
Add warning for OpenMP setting differences (#1358/#1382). When mlpack is compiled with OpenMP but another application is not (or vice versa), a compilation warning will now be issued.
Restructured loss functions in src/mlpack/methods/ann/ (#1365).
Add environments for reinforcement learning tests (#1368, #1370, #1329).
Allow single outputs for multiple timestep inputs for recurrent neural networks (#1348).
Add He and LeCun normal initializations for neural networks (#1342). Neural networks: add He and LeCun normal initializations (#1342), add FReLU and SELU activation functions (#1346, #1341), add alpha-dropout (#1349).

🔗 mlpack 3.0.0

2018-03-30

Speed and memory improvements for DBSCAN. –single_mode can now be used for situations where previously RAM usage was too high.
Bump minimum required version of Armadillo to 6.500.0.
Add automatically generated Python bindings. These have the same interface as the command-line programs.
Add deep learning infrastructure in src/mlpack/methods/ann/.
Add reinforcement learning infrastructure in src/mlpack/methods/reinforcement_learning/.
Add optimizers: AdaGrad, CMAES, CNE, FrankeWolfe, GradientDescent, GridSearch, IQN, Katyusha, LineSearch, ParallelSGD, SARAH, SCD, SGDR, SMORMS3, SPALeRA, SVRG.
Add hyperparameter tuning infrastructure and cross-validation infrastructure in src/mlpack/core/cv/ and src/mlpack/core/hpt/.
Fix bug in mean shift.
Add random forests (see src/mlpack/methods/random_forest).
Numerous other bugfixes and testing improvements.
Add randomized Krylov SVD and Block Krylov SVD.

🔗 mlpack 2.2.5

2017-08-25

Compilation fix for some systems (#1082).
Fix PARAM_INT_OUT() (#1100).

🔗 mlpack 2.2.4

2017-07-18

Speed and memory improvements for DBSCAN. –single_mode can now be used for situations where previously RAM usage was too high.
Fix bug in CF causing incorrect recommendations.

🔗 mlpack 2.2.3

2017-05-24

Bug fix for –predictions_file in mlpack_decision_tree program.

🔗 mlpack 2.2.2

2017-05-04

Install backwards-compatibility mlpack_allknn and mlpack_allkfn programs; note they are deprecated and will be removed in mlpack 3.0.0 (#992).
Fix RStarTree bug that surfaced on OS X only (#964).
Small fixes for MiniBatchSGD and SGD and tests.

🔗 mlpack 2.2.1

2017-04-13

Compilation fix for mlpack_nca and mlpack_test on older Armadillo versions (#984).

🔗 mlpack 2.2.0

2017-03-21

Bugfix for mlpack_knn program (#816).
Add decision tree implementation in methods/decision_tree/. This is very similar to a C4.5 tree learner.
Add DBSCAN implementation in methods/dbscan/.
Add support for multidimensional discrete distributions (#810, #830).
Better output for Log::Debug/Log::Info/Log::Warn/Log::Fatal for Armadillo objects (#895, #928).
Refactor categorical CSV loading with boost::spirit for faster loading (#681).

🔗 mlpack 2.1.1

2016-12-22

HMMs now use random initialization; this should fix some convergence issues (#828).
HMMs now initialize emissions according to the distribution of observations (#833).
Minor fix for formatted output (#814).
Fix DecisionStump to properly work with any input type.

🔗 mlpack 2.1.0

2016-10-31

Fixed CoverTree to properly handle single-point datasets.
Fixed a bug in CosineTree (and thus QUIC-SVD) that caused split failures for some datasets (#717).
Added mlpack_preprocess_describe program, which can be used to print statistics on a given dataset (#742).
Fix prioritized recursion for k-furthest-neighbor search (mlpack_kfn and the KFN class), leading to orders-of-magnitude speedups in some cases.
Bump minimum required version of Armadillo to 4.200.0.
Added simple Gradient Descent optimizer, found in src/mlpack/core/optimizers/gradient_descent/ (#792).
Added approximate furthest neighbor search algorithms QDAFN and DrusillaSelect in src/mlpack/methods/approx_kfn/, with command-line program mlpack_approx_kfn.

🔗 mlpack 2.0.3

2016-07-21

Added multiprobe LSH (#691). The parameter ‘T’ to LSHSearch::Search() can now be used to control the number of extra bins that are probed, as can the -T (–num_probes) option to mlpack_lsh.
Added the Hilbert R tree to src/mlpack/core/tree/rectangle_tree/ (#664). It can be used as the typedef HilbertRTree, and it is now an option in the mlpack_knn, mlpack_kfn, mlpack_range_search, and mlpack_krann command-line programs.
Added the mlpack_preprocess_split and mlpack_preprocess_binarize programs, which can be used for preprocessing code (#650, #666).
Added OpenMP support to LSHSearch and mlpack_lsh (#700).

🔗 mlpack 2.0.2

2016-06-20

Added the function LSHSearch::Projections(), which returns an arma::cube with each projection table in a slice (#663). Instead of Projection(i), you should now use Projections().slice(i).
A new constructor has been added to LSHSearch that creates objects using projection tables provided in an arma::cube (#663).
Handle zero-variance dimensions in DET (#515).
Add MiniBatchSGD optimizer (src/mlpack/core/optimizers/minibatch_sgd/) and allow its use in mlpack_logistic_regression and mlpack_nca programs.
Add better backtrace support from Grzegorz Krajewski for Log::Fatal messages when compiled with debugging and profiling symbols. This requires libbfd and libdl to be present during compilation.
CosineTree test fix from Mikhail Lozhnikov (#358).
Fixed HMM initial state estimation (#600).
Changed versioning macros __MLPACK_VERSION_MAJOR, __MLPACK_VERSION_MINOR, and __MLPACK_VERSION_PATCH to MLPACK_VERSION_MAJOR, MLPACK_VERSION_MINOR, and MLPACK_VERSION_PATCH. The old names will remain in place until mlpack 3.0.0.
Renamed mlpack_allknn, mlpack_allkfn, and mlpack_allkrann to mlpack_knn, mlpack_kfn, and mlpack_krann. The mlpack_allknn, mlpack_allkfn, and mlpack_allkrann programs will remain as copies until mlpack 3.0.0.
Add –random_initialization option to mlpack_hmm_train, for use when no labels are provided.
Add –kill_empty_clusters option to mlpack_kmeans and KillEmptyClusters policy for the KMeans class (#595, #596).

🔗 mlpack 2.0.1

2016-02-04

Fix CMake to properly detect when MKL is being used with Armadillo.
Minor parameter handling fixes to mlpack_logistic_regression (#504, #505).
Properly install arma_config.hpp.
Memory handling fixes for Hoeffding tree code.
Add functions that allow changing training-time parameters to HoeffdingTree class.
Fix infinite loop in sparse coding test.
Documentation spelling fixes (#501).
Properly handle covariances for Gaussians with large condition number (#496), preventing GMMs from filling with NaNs during training (and also HMMs that use GMMs).
CMake fixes for finding LAPACK and BLAS as Armadillo dependencies when ATLAS is used.
CMake fix for projects using mlpack’s CMake configuration from elsewhere (#512).

🔗 mlpack 2.0.0

2015-12-24

Removed overclustering support from k-means because it is not well-tested, may be buggy, and is (I think) unused. If this was support you were using, open a bug or get in touch with us; it would not be hard for us to reimplement it.
Refactored KMeans to allow different types of Lloyd iterations.
Added implementations of k-means: Elkan’s algorithm, Hamerly’s algorithm, Pelleg-Moore’s algorithm, and the DTNN (dual-tree nearest neighbor) algorithm.
Significant acceleration of LRSDP via the use of accu(a % b) instead of trace(a * b).
Added MatrixCompletion class (matrix_completion), which performs nuclear norm minimization to fill unknown values of an input matrix.
No more dependence on Boost.Random; now we use C++11 STL random support.
Add softmax regression, contributed by Siddharth Agrawal and QiaoAn Chen.
Changed NeighborSearch, RangeSearch, FastMKS, LSH, and RASearch API; these classes now take the query sets in the Search() method, instead of in the constructor.
Use OpenMP, if available. For now OpenMP support is only available in the DET training code.
Add support for predicting new test point values to LARS and the command-line lars program.
Add serialization support for Perceptron and LogisticRegression.
Refactor SoftmaxRegression to predict into an arma::Row<size_t> object, and add a softmax_regression program.
Refactor LSH to allow loading and saving of models.
ToString() is removed entirely (#487).
Add --input_model_file and --output_model_file options to appropriate machine learning algorithms.
Rename all executables to start with an “mlpack” prefix (#229).
Add HoeffdingTree and mlpack_hoeffding_tree, an implementation of the streaming decision tree methodology from Domingos and Hulten in 2000.

🔗 mlpack 1.0.12

2015-01-07

Switch to 3-clause BSD license (from LGPL).

🔗 mlpack 1.0.11

2014-12-11

Proper handling of dimension calculation in PCA.
Load parameter vectors properly for LinearRegression models.
Linker fixes for AugLagrangian specializations under Visual Studio.
Add support for observation weights to LinearRegression.
MahalanobisDistance<> now takes the root of the distance by default and therefore satisfies the triangle inequality (TakeRoot now defaults to true).
Better handling of optional Armadillo HDF5 dependency.
Fixes for numerous intermittent test failures.
math::RandomSeed() now sets the random seed for recent (>=3.930) Armadillo versions.
Handle Newton method convergence better for SparseCoding::OptimizeDictionary() and make maximum iterations a parameter.
Known bug: CosineTree construction may fail in some cases on i386 systems (#358).

🔗 mlpack 1.0.10

2014-08-29

Bugfix for NeighborSearch regression which caused very slow allknn/allkfn. Speeds are now restored to approximately 1.0.8 speeds, with significant improvement for the cover tree (#347).
Detect dependencies correctly when ARMA_USE_WRAPPER is not being defined (i.e., libarmadillo.so does not exist).
Bugfix for compilation under Visual Studio (#348).

🔗 mlpack 1.0.9

2014-07-28

GMM initialization is now safer and provides a working GMM when constructed with only the dimensionality and number of Gaussians (#301).
Check for division by 0 in Forward-Backward Algorithm in HMMs (#301).
Fix MaxVarianceNewCluster (used when re-initializing clusters for k-means) (#301).
Fixed implementation of Viterbi algorithm in HMM::Predict() (#303).
Significant speedups for dual-tree algorithms using the cover tree (#235, #314) including a faster implementation of FastMKS.
Fix for LRSDP optimizer so that it compiles and can be used (#312).
CF (collaborative filtering) now expects users and items to be zero-indexed, not one-indexed (#311).
CF::GetRecommendations() API change: now requires the number of recommendations as the first parameter. The number of users in the local neighborhood should be specified with CF::NumUsersForSimilarity().
Removed incorrect PeriodicHRectBound (#58).
Refactor LRSDP into LRSDP class and standalone function to be optimized (#305).
Fix for centering in kernel PCA (#337).
Added simulated annealing (SA) optimizer, contributed by Zhihao Lou.
HMMs now support initial state probabilities; these can be set in the constructor, trained, or set manually with HMM::Initial() (#302).
Added Nyström method for kernel matrix approximation by Marcus Edel.
Kernel PCA now supports using Nyström method for approximation.
Ball trees now work with dual-tree algorithms, via the BallBound<> bound structure (#307); fixed by Yash Vadalia.
The NMF class is now AMF<>, and supports far more types of factorizations, by Sumedh Ghaisas.
A QUIC-SVD implementation has returned, written by Siddharth Agrawal and based on older code from Mudit Gupta.
Added perceptron and decision stump by Udit Saxena (these are weak learners for an eventual AdaBoost class).
Sparse autoencoder added by Siddharth Agrawal.

🔗 mlpack 1.0.8

2014-01-06

Memory leak in NeighborSearch index-mapping code fixed (#298).
GMMs can be trained using the existing model as a starting point by specifying an additional boolean parameter to GMM::Estimate() (#296).
Logistic regression implementation added in methods/logistic_regression (see also #293).
L-BFGS optimizer now returns its function via Function().
Version information is now obtainable via mlpack::util::GetVersion() or the __MLPACK_VERSION_MAJOR, __MLPACK_VERSION_MINOR, and __MLPACK_VERSION_PATCH macros (#297).
Fix typos in allkfn and allkrann output.

🔗 mlpack 1.0.7

2013-10-04

Cover tree support for range search (range_search), rank-approximate nearest neighbors (allkrann), minimum spanning tree calculation (emst), and FastMKS (fastmks).
Dual-tree FastMKS implementation added and tested.
Added collaborative filtering package (cf) that can provide recommendations when given users and items.
Fix for correctness of Kernel PCA (kernel_pca) (#270).
Speedups for PCA and Kernel PCA (#198).
Fix for correctness of Neighborhood Components Analysis (NCA) (#279).
Minor speedups for dual-tree algorithms.
Fix for Naive Bayes Classifier (nbc) (#269).
Added a ridge regression option to LinearRegression (linear_regression) (#286).
Gaussian Mixture Models (gmm::GMM<>) now support arbitrary covariance matrix constraints (#283).
MVU (mvu) removed because it is known to not work (#183).
Minor updates and fixes for kernels (in mlpack::kernel).

🔗 mlpack 1.0.6

2013-06-13

Minor bugfix so that FastMKS gets built.

🔗 mlpack 1.0.5

2013-05-01

Speedups of cover tree traversers (#235).
Addition of rank-approximate nearest neighbors (RANN), found in src/mlpack/methods/rann/.
Addition of fast exact max-kernel search (FastMKS), found in src/mlpack/methods/fastmks/.
Fix for EM covariance estimation; this should improve GMM training time.
More parameters for GMM estimation.
Force GMM and GaussianDistribution covariance matrices to be positive definite, so that training converges much more often.
Add parameter for the tolerance of the Baum-Welch algorithm for HMM training.
Fix for compilation with clang compiler.
Fix for k-furthest-neighbor-search.

🔗 mlpack 1.0.4

2013-02-08

Force minimum Armadillo version to 2.4.2.
Better output of class types to streams; a class with a ToString() method implemented can be sent to a stream with operator«.
Change return type of GMM::Estimate() to double (#257).
Style fixes for k-means and RADICAL.
Handle size_t support correctly with Armadillo 3.6.2 (#258).
Add locality-sensitive hashing (LSH), found in src/mlpack/methods/lsh/.
Better tests for SGD (stochastic gradient descent) and NCA (neighborhood components analysis).

🔗 mlpack 1.0.3

2012-09-16

Remove internal sparse matrix support because Armadillo 3.4.0 now includes it. When using Armadillo versions older than 3.4.0, sparse matrix support is not available.
NCA (neighborhood components analysis) now support an arbitrary optimizer (#245), including stochastic gradient descent (#249).

🔗 mlpack 1.0.2

2012-08-15

Added density estimation trees, found in src/mlpack/methods/det/.
Added non-negative matrix factorization, found in src/mlpack/methods/nmf/.
Added experimental cover tree implementation, found in src/mlpack/core/tree/cover_tree/ (#157).
Better reporting of boost::program_options errors (#225).
Fix for timers on Windows (#212, #211).
Fix for allknn and allkfn output (#204).
Sparse coding dictionary initialization is now a template parameter (#220).

🔗 mlpack 1.0.1

2012-03-03

Added kernel principal components analysis (kernel PCA), found in src/mlpack/methods/kernel_pca/ (#74).
Fix for Lovasz-Theta AugLagrangian tests (#182).
Fixes for allknn output (#185, #186).
Added range search executable (#192).
Adapted citations in documentation to BibTeX; no citations in -h output (#195).
Stop use of ‘const char*’ and prefer ‘std::string’ (#176).
Support seeds for random numbers (#177).

🔗 mlpack 1.0.0

2011-12-17

Initial release. See any resolved tickets numbered less than #196 or execute this query: http://www.mlpack.org/trac/query?status=closed&milestone=mlpack+1.0.0