Re^2: Efficiently working with huge exponents (yeah)

Yeah, that's the same type of thing that Math::BigApprox makes much easier:

 $ time perl -MMath::BigApprox=c -le'print c(2)**1024000'
5.194693e+308254

real    0m0.021s
user    0m0.012s
sys     0m0.004s
[download]

And it makes a good guess at how many decimal places to show as well.

- tye

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Re^3: Efficiently working with huge exponents (yeah) by Laurent_R (Canon) on Mar 20, 2015 at 21:54 UTC
Thank you, tye ++, I did not know about this module until today, it looks very interesting, I'll look at it and at its code. I was only trying to give a very basic proof of concept to try to help the OP. Surely, your module offers much more than my poor basic attempts. Congrats for it. Je suis Charlie.	[reply]
Re^4: Efficiently working with huge exponents (yes) by tye (Sage) on Mar 20, 2015 at 22:48 UTC
No, I'm glad you laid out the fairly simple math that lets one do these types of calculations quickly and fairly easily. I just saw the opportunity to connect the two suggestions and thus 1) give people a quick intro to what Math::BigApprox is doing under the covers and 2) let the OP know that they don't have to do this by hand if this level of accuracy is acceptable. Thanks for showing the math that I didn't have/take the time to. :) - tye	[reply]
Re^3: Efficiently working with huge exponents (yeah) by wanna_code_perl (Friar) on Mar 21, 2015 at 13:55 UTC
Thanks to you both. While I'll probably just use Math::BigApprox for my current need, re-learning a little math never hurt anyone (much).	[reply]
Re^4: Efficiently working with huge exponents (yeah) by syphilis (Archbishop) on Mar 22, 2015 at 01:14 UTC
... I'll probably just use Math::BigApprox for my current need ... When the original post first appeared, I didn't notice any mention of perfect precision not being desired. Was that part of the post always there ? Anyway, just to correct my original reply to cater for perfect precision not being required: `perl -MMath::MPFR=:mpfr -le "Rmpfr_set_default_prec(28);print Math::MP +FR->new(2) ** 1024000;" 5.194693363e308254` [download] (In Math::MPFR, precision is specified in bits.) You can specify precision for your Math::BigFloat numbers, too - it's in the docs. Cheers, Rob	[reply] [d/l]
Re^5: Efficiently working with huge exponents (yeah) by wanna_code_perl (Friar) on Mar 22, 2015 at 13:04 UTC
When the original post first appeared, I didn't notice any mention of perfect precision not being desired. Was that part of the post always there ? Yes it was, and if it wasn't, I'd have clearly annotated the change. Thanks for the updated tip!	[reply]