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Sparse module: add a more flexible SparseMatrix::fillrand() function

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which allows to fill a matrix with random inner coordinates (makes sense
only when a very few coeffs are inserted per col/row)
This commit is contained in:
Gael Guennebaud
2008-12-11 18:26:24 +00:00
parent beabf008b0
commit 5015e48361
4 changed files with 68 additions and 5 deletions
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45
Eigen/src/Sparse/SparseMatrix.h
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@@ -131,6 +131,10 @@ class SparseMatrix
/** \returns the number of non zero coefficients */
inline int nonZeros() const { return m_data.size(); }
/** Initializes the filling process of \c *this.
* \param reserveSize approximate number of nonzeros
* Note that the matrix \c *this is zero-ed.
*/
inline void startFill(int reserveSize = 1000)
{
m_data.clear();
@@ -139,13 +143,16 @@ class SparseMatrix
m_outerIndex[i] = 0;
}
/**
*/
inline Scalar& fill(int row, int col)
{
const int outer = RowMajor ? row : col;
const int inner = RowMajor ? col : row;
// std::cout << " fill " << outer << "," << inner << "\n";
if (m_outerIndex[outer+1]==0)
{
// we start a new inner vector
int i = outer;
while (i>=0 && m_outerIndex[i]==0)
{
@@ -162,6 +169,42 @@ class SparseMatrix
return m_data.value(id);
}
/** Like fill() but with random inner coordinates.
*/
inline Scalar& fillrand(int row, int col)
{
const int outer = RowMajor ? row : col;
const int inner = RowMajor ? col : row;
if (m_outerIndex[outer+1]==0)
{
// we start a new inner vector
// nothing special to do here
int i = outer;
while (i>=0 && m_outerIndex[i]==0)
{
m_outerIndex[i] = m_data.size();
--i;
}
m_outerIndex[outer+1] = m_outerIndex[outer];
}
//
assert(m_outerIndex[outer+1] == m_data.size() && "invalid outer index");
int startId = m_outerIndex[outer];
int id = m_outerIndex[outer+1]-1;
m_outerIndex[outer+1]++;
m_data.resize(id+2);
while ( (id >= startId) && (m_data.index(id) > inner) )
{
m_data.index(id+1) = m_data.index(id);
m_data.value(id+1) = m_data.value(id);
--id;
}
m_data.index(id+1) = inner;
return (m_data.value(id+1) = 0);
}
inline void endFill()
{
int size = m_data.size();