public DenseMatrix GetCovarianceMatrix(ICaseFrame cases)
{
var data = new List <double[]>();
var cursor = cases.GetCaseCursor();
while (cursor.MoveNext())
{
var attributes = new double[cases.Schema.Count];
for (var i = 0; i < cases.Schema.Count; i++)
{
attributes[i] = cursor.GetAttribute <double>(cases.Schema[i]);
}
data.Add(attributes);
}
var dataMat = DenseMatrix.Build.DenseOfRowArrays(data);
var covMat = new DenseMatrix(dataMat.ColumnCount, dataMat.ColumnCount);
for (var i = 0; i < dataMat.ColumnCount; i++)
{
for (var j = 0; j < dataMat.ColumnCount; j++)
{
covMat[i, j] = dataMat.Column(i).Covariance(dataMat.Column(j));
}
}
return(covMat);
}
public WriteCursor(ICaseFrame caseFrame)
{
if (caseFrame == null)
{
throw new ArgumentNullException(nameof(caseFrame));
}
cursor = caseFrame.GetCaseCursor();
definition = new CaseDefinitionBuilder(typeof(TCase), cursor.Schema).Build();
idSetter = GenerateIdSetter();
solutionSetter = GenerateSolutionSetter();
setters = GenerateSetters();
}
private static IEnumerable <string> GetIds(ICaseFrame cases, bool shuffle)
{
var caseIds = new List <string>();
using (var cursor = cases.GetCaseCursor())
{
while (cursor.MoveNext())
{
caseIds.Add(cursor.GetId());
}
}
return(shuffle
? caseIds.OrderBy(a => Guid.NewGuid())
: (IEnumerable <string>)caseIds);
}
public override void Prepare(ICaseFrame cases)
{
if (cases == null)
{
throw new ArgumentNullException(nameof(cases));
}
BindSelectedAttributes(cases.Schema);
using (var cursor = cases.GetCaseCursor())
{
while (cursor.MoveNext())
{
foreach (var binding in AttributeBinding)
{
var getter = cursor.GetAttributeGetter <double>(cases.Schema[binding.Attribute]);
UpdateMinMax(binding.Binding, getter);
}
}
}
isPrepared = true;
}