CREATE_TABLE_FROM_MATRIX - export only non-empty cells
This procedure creates a user-visible table from a matrix and allows it to export only non-empty cells, that is, cells with non-zero values.
Usage
- CREATE_TABLE_FROM_MATRIX(mat_name,destination_table,sparse_only)
- Parameters
- mat_name
- The name of the matrix to be copied.
- destination_table
- The name of the table to be generated.
Details
Creates a table, owned by the caller, having the following schema: (row INTEGER, col INTEGER, value DOUBLE PRECISION). The created table contains the matrix data in a row/column/value representation. This hides the implementation details of NZMatrix and provides data to the user via a table representation. This procedure can export only nonempty cells, that is, cells with a non-zero value.
Examples
call nzm..shape('0,1,2,0,0,0,0,0,33',3,3,'A');
call nzm..create_table_from_matrix('A',
'my_rcv_dense',false);
call nzm..create_table_from_matrix('A',
'my_rcv_sparse',true);
select * from my_rcv_dense order by row,col;
select * from my_rcv_sparse order by row,col;
drop table my_rcv_dense;
drop table my_rcv_sparse;
call nzm..delete_matrix('A' );
SHAPE
-------
t
(1 row)
CREATE_TABLE_FROM_MATRIX
--------------------------
t
(1 row)
CREATE_TABLE_FROM_MATRIX
--------------------------
t
(1 row)
ROW | COL | VALUE
-----+-----+-------
1 | 1 | 0
1 | 2 | 1
1 | 3 | 2
2 | 1 | 0
2 | 2 | 0
2 | 3 | 0
3 | 1 | 0
3 | 2 | 0
3 | 3 | 33
(9 rows)
ROW | COL | VALUE
-----+-----+-------
1 | 2 | 1
1 | 3 | 2
3 | 3 | 33
(3 rows)
DELETE_MATRIX
---------------
t
(1 row)