/// <summary>
/// Create a dense matrix used in XGBoost.
/// </summary>
/// <param name="data">Matrix as a Float array</param>
/// <param name="nrow">Number of rows</param>
/// <param name="ncol">Number of columns</param>
/// <param name="labels">Labels</param>
/// <param name="missing">Missing value</param>
/// <param name="weights">Vector of weights (can be null)</param>
/// <param name="groups">Vector of groups (can be null)</param>
/// <param name="featureNames">Set names for features.</param>
/// <param name="featureTypes">Set types for features.</param>
public DMatrix(Float[] data, uint nrow, uint ncol, Float[] labels = null, Float missing = Float.NaN,
Float[] weights = null, uint[] groups = null,
IEnumerable <string> featureNames = null, IEnumerable <string> featureTypes = null)
{
#if (DEBUG)
_gcKeep = new GcKeep()
{
data = data,
labels = labels,
weights = weights,
groups = groups
};
#endif
WrappedXGBoostInterface.Check(WrappedXGBoostInterface.XGDMatrixCreateFromMat(data, nrow, ncol, missing, ref _handle));
if (labels != null)
{
SetLabel(labels, nrow);
}
if (weights != null)
{
SetWeight(weights, nrow);
}
if (groups != null)
{
SetGroups(groups, nrow);
}
_featureNames = featureNames == null ? null : featureNames.ToArray();
_featureTypes = featureTypes == null ? null : featureTypes.ToArray();
}
/// <summary>
/// Create a sparse matrix used in XGBoost.
/// </summary>
/// <param name="numColumn">number of features or columns</param>
/// <param name="indptr">Pointer to row headers</param>
/// <param name="indices">column indices</param>
/// <param name="data">Matrix as a Float array</param>
/// <param name="nrow">Rows in the matix</param>
/// <param name="nelem">Number of nonzero elements in the matrix</param>
/// <param name="labels">Labels</param>
/// <param name="weights">Vector of weights (can be null)</param>
/// <param name="groups">Vector of groups (can be null)</param>
/// <param name="featureNames">Set names for features.</param>
/// <param name="featureTypes">Set types for features.</param>
public DMatrix(/*bst_ulong*/ uint numColumn, /*size_t*/ ulong[] indptr, uint[] indices, Float[] data,
uint nrow, uint nelem, Float[] labels = null,
Float[] weights = null, uint[] groups = null,
IEnumerable <string> featureNames = null, IEnumerable <string> featureTypes = null)
{
Contracts.Assert(nrow + 1 == indptr.Length);
#if (DEBUG)
_gcKeep = new GcKeep()
{
indptr = indptr,
indices = indices,
data = data,
labels = labels,
weights = weights,
groups = groups
};
#endif
#if (XGB_EXTENDED)
WrappedXGBoostInterface.Check(WrappedXGBoostInterface.XGDMatrixCreateFromCSREx(indptr,
indices, data, (ulong)indptr.Length, nelem, numColumn, ref _handle));
#else
WrappedXGBoostInterface.Check(WrappedXGBoostInterface.XGDMatrixCreateFromCSR(indptr,
indices, data, (uint)indptr.Length, nelem, ref _handle));
#endif
if (labels != null)
{
SetLabel(labels, nrow);
}
if (weights != null)
{
SetWeight(weights, nrow);
}
if (groups != null)
{
SetGroups(groups, nrow);
}
_featureNames = featureNames == null ? null : featureNames.ToArray();
_featureTypes = featureTypes == null ? null : featureTypes.ToArray();
Contracts.Assert(nrow == (int)GetNumRows());
Contracts.Assert((int)GetNumCols() == numColumn);
}