Understanding the generator

[hgl71964]

Hello,

I am trying to understand the generator as in the PET paper.

To my understanding, the threshold parameter in the Generator::run() function defines the number of random test point that a legal mutant has to satisfy, as computed by the Generator::approx_equal() function.

The default threshold=0.7 results in, for example, sometimes a Matmul has 20 mutants, and sometimes has 28 mutants. Is this randomness intended?

If a legal mutant passes this test, how does the correction kernel generated? Is the correction kernel generated by the Generator?

Many Thanks,