public void DecomposeAxis()
{
var numberOfShapeFunctions = _knotValueVector.Length - _degree - 1;
var shapeFunctionSupports = new List <FunctionSupport>();
var indexFunction = 0;
for (int i = 0; i < numberOfShapeFunctions; i++)
{
shapeFunctionSupports.Add(new FunctionSupport
{
ID = indexFunction++,
Start = _knotValueVector[i],
End = _knotValueVector[i + _degree + 1]
});
}
var knots = _knotValueVector.CopyToArray().Distinct().ToList();
var axisElements = knots.Count() - 1;
var subdomainElements = (axisElements % _numberOfSubdomains == 0)
? axisElements / _numberOfSubdomains
: axisElements / _numberOfSubdomains + 1;
_decompositionIndices = new List <double>();
for (int i = 0; i < knots.Count() - 1; i += subdomainElements)
{
_decompositionIndices.Add(knots[i]);
}
_decompositionIndices.Add(knots[knots.Count - 1]);
var coarseKnotVector = new List <double>();
for (int i = 0; i < _degree; i++)
{
coarseKnotVector.Add(knots[0]);
}
coarseKnotVector.AddRange(_decompositionIndices);
for (int i = 0; i < _degree; i++)
{
coarseKnotVector.Add(knots[knots.Count - 1]);
}
_coarseKnotVector = coarseKnotVector.ToArray();
var numberOfCoarsePoints = coarseKnotVector.Count - _degree - 1;
_coarsePoints = new double[numberOfCoarsePoints];
for (int i = 0; i < numberOfCoarsePoints; i++)
{
var sum = 0.0;
for (int j = i + 1; j <= i + _degree; j++)
{
sum += coarseKnotVector[j];
}
_coarsePoints[i] = sum / _degree;
}
var shapeFunctionsIds = new List <int>();
shapeFunctionsIds.Add(0);
for (int i = 1; i < _decompositionIndices.Count - 1; i++)
{
var index = _decompositionIndices[i];
var functions = shapeFunctionSupports.Where(s => s.Start <index && s.End> index).ToArray();
var j = functions.Count() % 2 != 0 ? functions.Count() / 2 : functions.Count() / 2 - 1;
var id = functions[j].ID;
shapeFunctionsIds.Add(id);
}
shapeFunctionsIds.Add(numberOfShapeFunctions);
_subdomainIndices = new int[shapeFunctionsIds.Count - 1][];
for (int i = 0; i < shapeFunctionsIds.Count - 1; i++)
{
var indexCount = (shapeFunctionsIds[i] == 0)
? shapeFunctionsIds[i + 1] - shapeFunctionsIds[i] + 1
: shapeFunctionsIds[i + 1] - shapeFunctionsIds[i];
_subdomainIndices[i] = Enumerable.Range(shapeFunctionsIds[i], indexCount).ToArray();
}
}