Method resize

include/Eigen/src/SparseCore/SparseMatrix.h:730–745

Resizes the matrix to a \a rows x \a cols matrix and initializes it to zero. * * 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 reserve(), setZero() */

   * \sa reserve(), setZero()
   */
  void resize(Index rows, Index cols) {
    const Index outerSize = IsRowMajor ? rows : cols;
    m_innerSize = IsRowMajor ? cols : rows;
    m_data.clear();

    if ((m_outerIndex == 0) || (m_outerSize != outerSize)) {
      m_outerIndex = internal::conditional_aligned_realloc_new_auto<StorageIndex, true>(m_outerIndex, outerSize + 1,
                                                                                        m_outerSize + 1);
      m_outerSize = outerSize;
    }

    internal::conditional_aligned_delete_auto<StorageIndex, true>(m_innerNonZeros, m_outerSize);
    m_innerNonZeros = 0;

    std::fill_n(m_outerIndex, m_outerSize + 1, StorageIndex(0));
  }

  /** \internal
   * Resize the nonzero vector to \a size */