Re: probable bug of "ispower" function in GP

luis . gallardo on Thu, 12 Jan 2023 12:41:42 +0100

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Re: probable bug of "ispower" function in GP

To: Vincent Lefevre <vincent@vinc17.net>
Subject: Re: probable bug of "ispower" function in GP
From: luis.gallardo@math.cnrs.fr
Date: Thu, 12 Jan 2023 12:40:33 +0100
Cc: luis.gallardo@math.cnrs.fr, Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>, pari-dev@pari.math.u-bordeaux.fr, Luis.Gallardo@univ-brest.fr
Delivery-date: Thu, 12 Jan 2023 12:41:42 +0100
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Hi Vincent, Bill,


Apologies!

I misunderstood the definition of "ispower"!


I wanted a function that identify directly if some integer is a power of 2


cordially,


luis
***


Vincent Lefevre <vincent@vinc17.net> a écrit :

Hi,

On 2023-01-12 12:13:05 +0100, luis.gallardo@math.cnrs.fr wrote:

(01:00) gp > ispower(8,2)
%1 = 0
(01:00) gp > ispower(16,2)
%2 = 1
(01:00) gp > ispower(9,3)
%3 = 0
(01:00) gp > ispower(27,3)
%4 = 1
(01:01) gp > ispower(4,2)
%5 = 1
(01:01) gp >


These answers look fine. Where is the bug?

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Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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References:
- probable bug of "ispower" function in GP
  - From: luis.gallardo@math.cnrs.fr
- Re: probable bug of "ispower" function in GP
  - From: Vincent Lefevre <vincent@vinc17.net>

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