coordinate representation

[[concept]]

Coordinate (COO)rdinate Representation

$A$ can become a set of $|E|$ tuples of the form $(\text{row index},\text{column index},\text{value})$. So this matrix becomes the ordered set of these tuples, sorted by row and then column index.

This can be better from a memory perspective, but can still be quite large if we have a few nodes with high degree. A nice solution to this is to use compressed sparse row representation instead.

Example

12 & 0 & 26 & 0 \ 0 & 0 & 19 & 14 \ 26 & 19 & 0 & 0 \ 0 & 14 & 0 & 7 \end{bmatrix}$$

can become $(0,0,12),(0,2,26),(1,2,19),(1,3,14),(2,0,26),(2,1,19),(3,1,14),(3,3,7)$

Mentions

TABLE
FROM [[]]
 
FLATTEN choice(contains(artist, this.file.link), 1, "") + choice(contains(author, this.file.link), 1, "") + choice(contains(director, this.file.link), 1, "") + choice(contains(source, this.file.link), 1, "") as direct_source
 
WHERE !direct_source