Message 412172 - Python tracker

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Author	Carl.Friedrich.Bolz
Recipients	Carl.Friedrich.Bolz, Dennis Sweeney, tim.peters
Date	2022-01-30.20:01:02
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1643572862.88.0.292682188565.issue46558@roundup.psfhosted.org>
In-reply-to

Content
Somebody pointed me to V8's implementation of str(bigint) today: https://github.com/v8/v8/blob/main/src/bigint/tostring.cc They say that they can compute str(factorial(1_000_000)) (which is 5.5 million decimal digits) in 1.5s: https://twitter.com/JakobKummerow/status/1487872478076620800 As far as I understand the code (I suck at C++) they recursively split the bigint into halves using % 10^n at each recursion step, but pre-compute and cache the divisors' inverses.

Somebody pointed me to V8's implementation of str(bigint) today:

https://github.com/v8/v8/blob/main/src/bigint/tostring.cc

They say that they can compute str(factorial(1_000_000)) (which is 5.5 million decimal digits) in 1.5s:

https://twitter.com/JakobKummerow/status/1487872478076620800

As far as I understand the code (I suck at C++) they recursively split the bigint into halves using % 10^n at each recursion step, but pre-compute and cache the divisors' inverses.

History
Date	User	Action	Args
2022-01-30 20:01:02	Carl.Friedrich.Bolz	set	recipients: + Carl.Friedrich.Bolz, tim.peters, Dennis Sweeney
2022-01-30 20:01:02	Carl.Friedrich.Bolz	set	messageid: <1643572862.88.0.292682188565.issue46558@roundup.psfhosted.org>
2022-01-30 20:01:02	Carl.Friedrich.Bolz	link	issue46558 messages
2022-01-30 20:01:02	Carl.Friedrich.Bolz	create