Is the following implemented by a sparse matrix representation? type Graph n w = Array (n, n) (Maybe w)
Looks like the graph is represented by an adjacency matrix, where the element at (a, b) tells you whether there is an edge from node a to node b with weight x or not by having the value (Just x) or Nothing, respectively. Whether the matrix is sparse depends on the data, i.e. how many edges are in the graph. But perhaps I misunderstood your question. Thomas Am 09.07.2013 23:26, schrieb KC:
type Graph n w = Array (n,n) (Maybe w)
The standard array types, such as "Array (n,n) (Maybe w)" will be implemented as a dense array. If you want to use a sparse matrix, you will explicitly have to ask for it. For instance by using something like "IntMap (IntMap w)" or "Map (n,n) w" or "Array n (IntMap w)". Each of these representations is slightly different, and there will be different trade-offs. Twan On 09/07/13 23:26, KC wrote:
Is the following implemented by a sparse matrix representation? type Graph n w = Array (n,n) (Maybe w)
-- -- Regards, KC
Thank you :)
On Wed, Jul 10, 2013 at 8:33 AM, Twan van Laarhoven
The standard array types, such as "Array (n,n) (Maybe w)" will be implemented as a dense array. If you want to use a sparse matrix, you will explicitly have to ask for it. For instance by using something like "IntMap (IntMap w)" or "Map (n,n) w" or "Array n (IntMap w)". Each of these representations is slightly different, and there will be different trade-offs.
Twan
On 09/07/13 23:26, KC wrote:
Is the following implemented by a sparse matrix representation?
type Graph n w = Array (n,n) (Maybe w)
-- -- Regards, KC
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-- -- Regards, KC
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Twan van Laarhoven