PARI's commands

[science_man_88]

Originally Posted by CRGreathouse

Yes -- natural1 would take a long, long time to do that. It took 4:59.8 to do 10^5; based on curve-fitting with smaller numbers I estimate it would take about a month for it to do 10^7.

yeah with my isprime check and forstep loop put/editted in this seems even faster as it reduces the work. I was just trying:

natural2(10000000)

which is natural with those replacements etc. it comes back with:

***   last result computed in 7,344 ms.

and even when i tried 100 million I was able to get every prime in under 1 min 20 I think.

[CRGreathouse]

Let me see the code.

[science_man_88]

Originally Posted by CRGreathouse

Let me see the code.

natural2(N)=my(l=List());forstep(n=5,N,[2,4],if(isprime(n),listput(l,n)));Vec(l);

did I mention I'm running cityville on Facebook as well lol.

[science_man_88]

(12:43)>##
  ***   last result computed in 1mn, 18,328 ms.
(12:43)>natural2(100000000)

pretty quick.

[CRGreathouse]

Originally Posted by science_man_88

natural2(N)=my(l=List());forstep(n=5,N,[2,4],if(isprime(n),listput(l,n)));Vec(l);

did I mention I'm running cityville on Facebook as well lol.

So it's based on the fast natural, not the slow natural1. No surprise it's faster than natural1.

[science_man_88]

Originally Posted by CRGreathouse

So it's based on the fast natural, not the slow natural1. No surprise it's faster than natural1.

last I checked it was faster than the fast natural

[CRGreathouse]

Originally Posted by science_man_88

last I checked it was faster than the fast natural

Sure -- it doesn't add as many numbers.

[science_man_88]

Originally Posted by CRGreathouse

Sure -- it doesn't add as many numbers.

outside of the fact that the default list seems faster if I could get it fast enough could it ever replace the current one ?

[CRGreathouse]

Originally Posted by science_man_88

outside of the fact that the default list seems faster if I could get it fast enough could it ever replace the current one ?

I'm not sure what you're asking.

If the question is, "could some version of natural2 replace natural?", I'm not sure how to answer -- natural2 gives different output from natural, and natural itself is just a less-efficient version of vector(N,i,i) which doesn't have many uses anyway.

If the question is, "could some version of List replace List?", it's possible -- but that would have to be in C/PARI not gp.

[science_man_88]

Originally Posted by CRGreathouse

I'm not sure what you're asking.

If the question is, "could some version of natural2 replace natural?", I'm not sure how to answer -- natural2 gives different output from natural, and natural itself is just a less-efficient version of vector(N,i,i) which doesn't have many uses anyway.

If the question is, "could some version of List replace List?", it's possible -- but that would have to be in C/PARI not gp.

I'm talking

default(primelimit,x)

seems faster than this script .

[CRGreathouse]

Originally Posted by science_man_88

I'm talking

default(primelimit,x)

seems faster than this script .

Wow, that was random.

Sure. So is the program

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