Parameters: |
-
X : array of shape (n_samples, n_features) -
Data matrix -
dictionary : array of shape (n_components, n_features) -
The dictionary matrix against which to solve the sparse coding of the data. Some of the algorithms assume normalized rows for meaningful output. -
gram : array, shape=(n_components, n_components) -
Precomputed Gram matrix, dictionary * dictionary’ -
cov : array, shape=(n_components, n_samples) -
Precomputed covariance, dictionary’ * X -
algorithm : {‘lasso_lars’, ‘lasso_cd’, ‘lars’, ‘omp’, ‘threshold’} -
lars: uses the least angle regression method (linear_model.lars_path) lasso_lars: uses Lars to compute the Lasso solution lasso_cd: uses the coordinate descent method to compute the Lasso solution (linear_model.Lasso). lasso_lars will be faster if the estimated components are sparse. omp: uses orthogonal matching pursuit to estimate the sparse solution threshold: squashes to zero all coefficients less than alpha from the projection dictionary * X’ -
n_nonzero_coefs : int, 0.1 * n_features by default -
Number of nonzero coefficients to target in each column of the solution. This is only used by algorithm=’lars’ and algorithm=’omp’ and is overridden by alpha in the omp case. -
alpha : float, 1. by default -
If algorithm=’lasso_lars’ or algorithm=’lasso_cd’ , alpha is the penalty applied to the L1 norm. If algorithm=’threshold’ , alpha is the absolute value of the threshold below which coefficients will be squashed to zero. If algorithm=’omp’ , alpha is the tolerance parameter: the value of the reconstruction error targeted. In this case, it overrides n_nonzero_coefs . -
copy_cov : boolean, optional -
Whether to copy the precomputed covariance matrix; if False, it may be overwritten. -
init : array of shape (n_samples, n_components) -
Initialization value of the sparse codes. Only used if algorithm=’lasso_cd’ . -
max_iter : int, 1000 by default -
Maximum number of iterations to perform if algorithm=’lasso_cd’ . -
n_jobs : int or None, optional (default=None) -
Number of parallel jobs to run. None means 1 unless in a joblib.parallel_backend context. -1 means using all processors. See Glossary for more details. -
check_input : boolean, optional -
If False, the input arrays X and dictionary will not be checked. -
verbose : int, optional -
Controls the verbosity; the higher, the more messages. Defaults to 0. -
positive : boolean, optional -
Whether to enforce positivity when finding the encoding. |