Hello!
I found the source file. I have also learned that the .f9 was calculated with Crystal17, and that malloc happened in Props17, not in Props23 (I am likewise not sure whether the calculation that failed for my colleague was done using v17 or v23). This might have been a limitation of the machine that I was using, because the same calculation didn't crash with NEWK 36 72.
malloc.d12

I am sorry if that turns out irrelevant, and of no use in the current version of Crystal.

Hi andrejsc,
There is no "hardcoded" switch in the TOLINTEG keyword, I suspect that the quote from the manual comes from the "old days", when a threshold of \( 10^{-20} \) was considered absurdly small. However, with advances in hardware and the increasingly complex structures we want to compute, such thresholds are sometimes necessary.

A small note: don't warry about going past machine precision with these small numbers. All evaluations of integral thresholds in the code are performed at the logaritmic level (ie only on the exponent), so you should be fine even with a value of 1 million in TOLINTEG (though maybe not fine in terms of computation time)