protected void computeStatsFillModel(
PCAModel pca, DataInfo dinfo, SingularValueDecomposition svd, Gram gram, long nobs) {
// Save adapted frame info for scoring later
pca._output._normSub = dinfo._normSub == null ? new double[dinfo._nums] : dinfo._normSub;
if (dinfo._normMul == null) {
pca._output._normMul = new double[dinfo._nums];
Arrays.fill(pca._output._normMul, 1.0);
} else pca._output._normMul = dinfo._normMul;
pca._output._permutation = dinfo._permutation;
pca._output._nnums = dinfo._nums;
pca._output._ncats = dinfo._cats;
pca._output._catOffsets = dinfo._catOffsets;
double dfcorr = nobs / (nobs - 1.0);
double[] sval = svd.getSingularValues();
pca._output._std_deviation = new double[_parms._k]; // Only want first k standard deviations
for (int i = 0; i < _parms._k; i++) {
sval[i] =
dfcorr
* sval[
i]; // Degrees of freedom = n-1, where n = nobs = # row observations processed
pca._output._std_deviation[i] = Math.sqrt(sval[i]);
}
double[][] eigvec = svd.getV().getArray();
pca._output._eigenvectors_raw =
new double[eigvec.length][_parms._k]; // Only want first k eigenvectors
for (int i = 0; i < eigvec.length; i++)
System.arraycopy(eigvec[i], 0, pca._output._eigenvectors_raw[i], 0, _parms._k);
pca._output._total_variance =
dfcorr * gram.diagSum(); // Since gram = X'X/n, but variance requires n-1 in denominator
buildTables(pca, dinfo.coefNames());
}
// Main worker thread
@Override
protected void compute2() {
PCAModel model = null;
DataInfo dinfo = null;
DataInfo xinfo = null;
Frame x = null;
try {
init(true); // Initialize parameters
_parms.read_lock_frames(PCA.this); // Fetch & read-lock input frames
if (error_count() > 0)
throw new IllegalArgumentException("Found validation errors: " + validationErrors());
// The model to be built
model = new PCAModel(dest(), _parms, new PCAModel.PCAOutput(PCA.this));
model.delete_and_lock(_key);
if (_parms._pca_method == PCAParameters.Method.GramSVD) {
dinfo =
new DataInfo(
Key.make(),
_train,
null,
0,
_parms._use_all_factor_levels,
_parms._transform,
DataInfo.TransformType.NONE,
/* skipMissing */ true, /* missingBucket */
false, /* weights */
false, /* offset */
false, /* intercept */
false);
DKV.put(dinfo._key, dinfo);
// Calculate and save Gram matrix of training data
// NOTE: Gram computes A'A/n where n = nrow(A) = number of rows in training set (excluding
// rows with NAs)
GramTask gtsk = new Gram.GramTask(self(), dinfo).doAll(dinfo._adaptedFrame);
Gram gram =
gtsk._gram; // TODO: This ends up with all NaNs if training data has too many missing
// values
assert gram.fullN() == _ncolExp;
// Compute SVD of Gram A'A/n using JAMA library
// Note: Singular values ordered in weakly descending order by algorithm
Matrix gramJ = new Matrix(gtsk._gram.getXX());
SingularValueDecomposition svdJ = gramJ.svd();
computeStatsFillModel(model, dinfo, svdJ, gram, gtsk._nobs);
} else if (_parms._pca_method == PCAParameters.Method.Power) {
SVDModel.SVDParameters parms = new SVDModel.SVDParameters();
parms._train = _parms._train;
parms._ignored_columns = _parms._ignored_columns;
parms._ignore_const_cols = _parms._ignore_const_cols;
parms._score_each_iteration = _parms._score_each_iteration;
parms._use_all_factor_levels = _parms._use_all_factor_levels;
parms._transform = _parms._transform;
parms._nv = _parms._k;
parms._max_iterations = _parms._max_iterations;
parms._seed = _parms._seed;
// Calculate standard deviation and projection as well
parms._only_v = false;
parms._u_name = _parms._loading_name;
parms._keep_u = _parms._keep_loading;
SVDModel svd = null;
SVD job = null;
try {
job = new EmbeddedSVD(_key, _progressKey, parms);
svd = job.trainModel().get();
if (job.isCancelledOrCrashed()) PCA.this.cancel();
} finally {
if (job != null) job.remove();
if (svd != null) svd.remove();
}
// Recover PCA results from SVD model
computeStatsFillModel(model, svd);
} else if (_parms._pca_method == PCAParameters.Method.GLRM) {
GLRMModel.GLRMParameters parms = new GLRMModel.GLRMParameters();
parms._train = _parms._train;
parms._ignored_columns = _parms._ignored_columns;
parms._ignore_const_cols = _parms._ignore_const_cols;
parms._score_each_iteration = _parms._score_each_iteration;
parms._transform = _parms._transform;
parms._k = _parms._k;
parms._max_iterations = _parms._max_iterations;
parms._seed = _parms._seed;
parms._recover_svd = true;
parms._loss = GLRMModel.GLRMParameters.Loss.L2;
parms._gamma_x = 0;
parms._gamma_y = 0;
GLRMModel glrm = null;
GLRM job = null;
try {
job = new EmbeddedGLRM(_key, _progressKey, parms);
glrm = job.trainModel().get();
if (job.isCancelledOrCrashed()) PCA.this.cancel();
} finally {
if (job != null) job.remove();
if (glrm != null) {
glrm._parms._loading_key.get().delete();
glrm.remove();
}
}
// Recover PCA results from GLRM model
computeStatsFillModel(model, glrm);
}
model.update(self());
update(1);
done();
} catch (Throwable t) {
Job thisJob = DKV.getGet(_key);
if (thisJob._state == JobState.CANCELLED) {
Log.info("Job cancelled by user.");
} else {
t.printStackTrace();
failed(t);
throw t;
}
} finally {
_parms.read_unlock_frames(PCA.this);
if (model != null) model.unlock(_key);
if (dinfo != null) dinfo.remove();
if (xinfo != null) xinfo.remove();
if (x != null && !_parms._keep_loading) x.delete();
}
tryComplete();
}
