From: Alan Braslau via ntg-context <ntg-context@ntg.nl>
To: Hans Hagen via ntg-context <ntg-context@ntg.nl>
Cc: Alan Braslau <alan.braslau@icloud.com>
Subject: Re: atan2 function
Date: Fri, 14 Oct 2022 08:40:01 -0600 [thread overview]
Message-ID: <20221014084001.4ae2940e@boo.my.domain> (raw)
In-Reply-To: <bd569b68-b996-caee-40ac-1e0ca0330d10@xs4all.nl>
On Fri, 14 Oct 2022 10:07:19 +0200
Hans Hagen via ntg-context <ntg-context@ntg.nl> wrote:
> So you suggest to add atantwo? As side note, you can redure your
> definition to:
>
> vardef atantwo(expr dy, dx) =
> if dx == 0 :
> if dy < 0 : - fi pi / 2
> else :
> atan(dy/dx) if dx > 0 : if dy < 0 : - else : + fi pi fi
> fi
> enddef ;
>
> going further makes us end up in an one-line obscurity
An absurdity, as further discussion on this thread has shown:
atan is derived from angle, which is essentially atan2.
There is no need to circle around.
As a side point, I now use MP doubleprecision mode by default, although
I do believe that it is still preferable to use classic scaled integer
mode (and minifun) for text graphical embellishments. The only
practical point to consider when using doubleprecision mode for me is
the need to explicitly use format with "decimal i" to round the text
rendering of numbers.
Alan
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next prev parent reply other threads:[~2022-10-14 14:40 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-13 5:40 Thangalin via ntg-context
2022-10-13 6:42 ` Max Chernoff via ntg-context
2022-10-13 19:51 ` Thangalin via ntg-context
2022-10-14 0:35 ` Max Chernoff via ntg-context
2022-10-14 8:07 ` Hans Hagen via ntg-context
2022-10-14 14:40 ` Alan Braslau via ntg-context [this message]
2022-10-14 18:59 ` Thangalin via ntg-context
2022-10-14 22:42 ` Alan Braslau via ntg-context
2022-10-14 23:09 ` Thangalin via ntg-context
2022-10-15 1:22 ` Alan Braslau via ntg-context
2022-10-14 12:26 ` Alan Braslau via ntg-context
2022-10-14 12:58 ` Taco Hoekwater via ntg-context
2022-10-14 13:05 ` luigi scarso via ntg-context
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