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Richard in Reading on Wed, 24 Apr 2013 01:31:40 +0200
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Surprising behaviour of sqrt() on squares of integers
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- To: pari-users@pari.math.u-bordeaux1.fr
- Subject: Surprising behaviour of sqrt() on squares of integers
- From: Richard in Reading <richard_in_reading@yahoo.co.uk>
- Date: Wed, 24 Apr 2013 00:31:27 +0100 (BST)
- Delivery-date: Wed, 24 Apr 2013 01:31:40 +0200
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This is just a toy example but there are other real situation where it's annoying that PARI doesn't recognize when you want to take a square root of the square of an integer and return an integer.
Is there some justification for this or is it worth me reporting it as a bug.
? Mod(5,sqrt(9))
*** at top-level: Mod(5,sqrt(denominat
*** ^--------------------
*** Mod: forbidden division t_INT % t_REAL.
*** Break loop: type 'break' to go back to GP
? sqrt(2^256)
%17 = 3.4028236692093846346337460743176821146 E38
? 2^128
%18 = 340282366920938463463374607431768211456
The above should return the same value in my opinion.
Richard Heylen