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.. _csr_table:

==================================
Compressed Sparse Rows (CSR) Table
==================================

``csr_table`` class is a subtype of a table type,
for which the following is true:

- All the columns have the same :capterm:`data type <Data type>`.
- The data within the table is sparse and stored in a 3-array format.
- The arrays describe the sparse matrix :math:`A` as follows:

        - The array values contain non-zero elements of the matrix row-by-row.
        - The element number ``j`` of the ``columns_indices`` array encodes
          the column index in the matrix :math:`A` for the jth element
          of the array values.
        - The element number ``i`` of the ``row_offsets`` array encodes
          the index in the array values corresponding to the first non-zero
          element in rows indexed ``i`` or greater.
          The last element in the array ``row_offsets`` encodes the number
          of non-zero elements in the matrix :math:`A`.

        |short_name| supports zero-based and one-based indexing.

.. figure:: ./images/zero-based-csr.png
  :width: 600
  :alt:

  Compressed Sparse Row (CSR) data format with zero-based indexing.

---------------------
Programming Interface
---------------------

Refer to :ref:`API Reference: Compressed Sparse Rows Table <api_csr_table>`
to learn more.