scipy.sparse.
vstack#
- scipy.sparse.vstack(blocks, format=None, dtype=None)[source]#
- Stack sparse arrays vertically (row wise) - Parameters:
- blocks
- sequence of sparse arrays with compatible shapes 
- formatstr, optional
- sparse format of the result (e.g., “csr”) by default an appropriate sparse array format is returned. This choice is subject to change. 
- dtypedtype, optional
- The data-type of the output array. If not given, the dtype is determined from that of blocks. 
 
- Returns:
- new_arraysparse matrix or array
- If any block in blocks is a sparse array, return a sparse array. Otherwise return a sparse matrix. - If you want a sparse array built from blocks that are not sparse arrays, use - block(vstack(blocks))or convert one block e.g. blocks[0] = csr_array(blocks[0]).
 
 - See also - hstack
- stack sparse matrices horizontally (column wise) 
 - Examples - >>> from scipy.sparse import coo_array, vstack >>> A = coo_array([[1, 2], [3, 4]]) >>> B = coo_array([[5, 6]]) >>> vstack([A, B]).toarray() array([[1, 2], [3, 4], [5, 6]])