CoinBLAS VS Oat++

When you consider that a graph and a matrix are isomorphic, doing vector matrix multiplication takes a vector with a set value, say row 4, and multiplies it by a matrix where row 4 has values present that represent edges to the nodes that are adjacent to it (ie "adjacency" matrix). The result is a vector with the next "step" in a BFS across the graph, do that in a loop and you step across the whole graph.

A cool result of this is, for example, taking an adjacency matrix and squaring it is the "Friend of a Friend" graph. It takes every node/row and multiplies it by itself, returning a matrix that are adjacent to the adjacencies of each node, ie, the friends (adjacencies of the adjacencies) of friends (adjacencies) of the nodes.

Deeper traversal are just higher nodes, a matrix cubed are the friends of the friends of the friends.

A picture is worth a thousand words, see figure 7 of this paper:

https://arxiv.org/pdf/1606.05790.pdf

Also check out figure 8, this shows how incidence matrices can work to represent hyper and multi graphs. An pair of incidence matrices reprsent two graphs, one from nodes to edges and the other from edges to nodes, these are n by m and m by n. When you multiply them, you get a square adjacency matrix that "projects" the incidence into an adjacency. This can be used to collapse hypergraphs into simple graphs that use different semirings to combine the multiple edges.

For some pretty pictures of this kind of stuff, check out CoinBLAS (note I am not a crypto-bro, it was just a very handy extremely large multi-graph that I could easily download in chunks to play with):

https://github.com/Graphegon/CoinBLAS/

Python wrapper around The GraphBLAS API:

https://github.com/michelp/pygraphblas

For an upcoming paper we've open sourced using pygraphblas to analyse the bitcoin graph using the GAP benchmarks on a server with 1TB of RAM:

https://github.com/Graphegon/CoinBLAS

I looked at oatpp and drogon, which are both great, but feel too high-level for my purposes. I tried drogon and got something working, but it feels like too much for my requirements, as in particular I'd like to slot in my choice of Json and message-body handling. C.f. the simple approach in Crow, which I easily understand and build on.

With the right libraries, C++ could be a good fit for applications that want to expose a fast web API to things that need lots of compute (simulators, for instance) or I/O (interactive editing of large datasets). Projects like Oat++ and Crow give me hope that we might see such an ecosystem develop.

Lots of other options have been mentioned, but I'll throw Oat++ into the mix. I used it for this purpose and it was reasonably painless.

https://github.com/oatpp/oatpp +WASM ;)

cd "some/temp/path/for/repositories" git clone https://github.com/oatpp/oatpp.git cd oatpp mkdir build && cd build cmake .. (sudo) make install

Maybe use something like https://oatpp.io to create a REST API: C++ in the backend with this library to create a REST server, and the JavaScript/TypeScript frontend to ask for the information.

I've used OATPP ( https://github.com/oatpp/oatpp ) which worked nicely for setting up simple rest interfaces. Supports things like swagger & websockets out of the box. It's also on Conan which is nice if you use cmake. I can't speak to it's performance but it has about a 1mb binary size footprint.

As for your web problem, I have only used https://oatpp.io/ in the past but I'm sure there are more frameworks like that on the internet.