public static MatrixFEM GenerateMatrixFEM_WithStDerative(UniversalDeriative universalDeriative = UniversalDeriative.Without)
{
MatrixFEM matrix = new MatrixFEM();
for (var i = 0; i < MatrixFEM.N; ++i)
{
matrix[0, i] = func_N1(UniversalElement.IntegralPoints[i].Xi, UniversalElement.IntegralPoints[i].Eta, universalDeriative);
matrix[1, i] = func_N2(UniversalElement.IntegralPoints[i].Xi, UniversalElement.IntegralPoints[i].Eta, universalDeriative);
matrix[2, i] = func_N3(UniversalElement.IntegralPoints[i].Xi, UniversalElement.IntegralPoints[i].Eta, universalDeriative);
matrix[3, i] = func_N4(UniversalElement.IntegralPoints[i].Xi, UniversalElement.IntegralPoints[i].Eta, universalDeriative);
}
return(matrix);
}
static Double func_N4(Double xi, Double eta, UniversalDeriative universalDeriative = UniversalDeriative.Without)
{
Double value = 0;
switch (universalDeriative)
{
case UniversalDeriative.Without:
value = 0.25f * (1 - xi) * (1 + eta);
break;
case UniversalDeriative.DerEta:
value = 0.25f * (1 - xi);
break;
case UniversalDeriative.DerXi:
value = -0.25f * (1 + eta);
break;
}
return(value);
}
