void
PenaltyMP_FE::determineTangent(void)
{
// first determine [C] = [-I [Ccr]]
C->Zero();
const Matrix &constraint = theMP->getConstraint();
int noRows = constraint.noRows();
int noCols = constraint.noCols();
for (int j=0; j<noRows; j++)
(*C)(j,j) = -1.0;
for (int i=0; i<noRows; i++)
for (int j=0; j<noCols; j++)
(*C)(i,j+noRows) = constraint(i,j);
// now form the tangent: [K] = alpha * [C]^t[C]
// *(tang) = (*C)^(*C);
// *(tang) *= alpha;
// THIS IS A WORKAROUND UNTIL WE GET addMatrixTransposeProduct() IN
// THE Matrix CLASS OR UNROLL THIS COMPUTATION
int rows = C->noRows();
int cols = C->noCols();
Matrix CT(cols,rows);
const Matrix &Cref = *C;
// Fill in the transpose of C
for (int k = 0; k < cols; k++)
for (int l = 0; l < rows; l++)
CT(k,l) = Cref(l,k);
// Compute alpha*(C^*C)
tang->addMatrixProduct(0.0, CT, Cref, alpha);
}
//[]运算符重载，非const
String::Cref String::operator[](int i)
{
check(i);
return Cref(*this,i);
}
