docstr: block_diag with sparse matrices 
docstr_tok: ["block_diag","with","sparse","matrices"]
code: def test_block_diag_sparse_matrices(self):
      """block_diag with sparse matrices"""
  
      sparse_col_matrices = [
          coo_matrix(([[1, 2, 3]]), shape=(1, 3)),
          coo_matrix(([[4, 5]]), shape=(1, 2)),
      ]
      block_sparse_cols_matrices = construct.block_diag(
          sparse_col_matrices
      )
      assert_equal(
          block_sparse_cols_matrices.todense(),
          matrix([[1, 2, 3, 0, 0], [0, 0, 0, 4, 5]]),
      )
  
      sparse_row_matrices = [
          coo_matrix(([[1], [2], [3]]), shape=(3, 1)),
          coo_matrix(([[4], [5]]), shape=(2, 1)),
      ]
      block_sparse_row_matrices = construct.block_diag(
          sparse_row_matrices
      )
      assert_equal(
          block_sparse_row_matrices.todense(),
          matrix([[1, 0], [2, 0], [3, 0], [0, 4], [0, 5]]),
      )
  
imports: import numpy
  from numpy import array
  from numpy.testing import assert_equal, assert_, assert_array_equal, assert_array_almost_equal_nulp
  import pytest
  from pytest import raises
  from scipy._lib._testutils import check_free_memory
  from scipy._lib._util import check_random_state
  from scipy.sparse import csr_matrix, coo_matrix, construct
  from scipy.sparse.construct import rand
  from scipy.sparse.sputils import matrix
label_desc: Use image node_id 23 for calling the TestConstructUtils obj's underlying member method code with example usage: obj.test_block_diag_sparse_matrices() without return types