Solver returns false solution with overflow

[calixphd]

Objective of issue:

Lava version:

• [ ] 0.3.0 (feature release)
• [ ] 0.2.1 (bug fixes)
• [x] 0.2.0 (current version)
• [ ] 0.1.2

I'm submitting a ...

• [x] bug report
• [ ] feature request
• [ ] documentation request

Current behavior:

Expected behavior:

Steps to reproduce:

Related code:

insert short code snippets here

Other information:

insert the output from lava debug here

[calixphd]

This error was observed when the QUBO matrix is scaled with w_mult = 40. Host: LMT notified network reached target cost: -3087632 Host: LMT notified network reached target cost: -3087632 Host: stopping simulation at step: 4045

Basically any set of hyperparameters will return a false solution.

[phstratmann]

To add some info: If the synaptic weights are high, then the solver integrates the cost, gets to a very high value, and shows an integer overflow. As a result, it assumes that it found a very good solution (-high number) and stops. Maybe integer overflow in the dendritic accumulator of the cost integrator?