Method setZero

cpp/src/external/eigen/src/SparseCore/SparseMatrix.h:246–252

Removes all non zeros but keep allocated memory * * This function does not free the currently allocated memory. To release as much as memory as possible, * call \code mat.data().squeeze(); \endcode after resizing it. * * \sa resize(Index,Index), data() */

      * \sa resize(Index,Index), data()
      */
    inline void setZero()
    {
      m_data.clear();
      memset(m_outerIndex, 0, (m_outerSize+1)*sizeof(StorageIndex));
      if(m_innerNonZeros)
        memset(m_innerNonZeros, 0, (m_outerSize)*sizeof(StorageIndex));
    }

    /** Preallocates \a reserveSize non zeros.
      *