Method reserve

include/Eigen/src/SparseCore/SparseMatrix.h:314–317

Preallocates \a reserveSize non zeros. * * Precondition: the matrix must be in compressed mode. */

   *
   * Precondition: the matrix must be in compressed mode. */
  inline void reserve(Index reserveSize) {
    eigen_assert(isCompressed() && "This function does not make sense in non compressed mode.");
    m_data.reserve(reserveSize);
  }

#ifdef EIGEN_PARSED_BY_DOXYGEN
  /** Preallocates \a reserveSize[\c j] non zeros for each column (resp. row) \c j.