Re: arithmetic operations with t

Christian Krause on Sat, 29 Oct 2022 08:54:20 +0200

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Re: arithmetic operations with t_INFINITY

To: Max Alekseyev <maxale@gmail.com>
Subject: Re: arithmetic operations with t_INFINITY
From: Christian Krause <me@ckrause.org>
Date: Sat, 29 Oct 2022 08:53:08 +0200
Cc: pari-users@pari.math.u-bordeaux.fr
Delivery-date: Sat, 29 Oct 2022 08:54:20 +0200
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If you consider 1/0 as the limit of 1/x from the positive side of the x-axis, it would be +oo. If you consider it as the limit from the left side, it would be -oo. The choice for +oo seems arbitrary in this case.

On Fri 28. Oct 2022 at 22:14, Max Alekseyev <maxale@gmail.com> wrote:

It seems reasonable to expect that "123 + oo" or "-567 * oo" should evaluate in "+oo" and "-oo", respectively, but at the moment they both result in the "forbidden" error.
Can support of basic arithmetic operations for t_INFINITY be added? Of course, undefined operations such as "oo - oo" should still produce an error.
Thank you!

Max

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