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From: "Lawrence Velázquez" <vq@larryv.me>
To: Ray Andrews <rayandrews@eastlink.ca>
Cc: zsh-users@zsh.org
Subject: Re: run time of math problem
Date: Fri, 19 Mar 2021 23:59:37 -0400	[thread overview]
Message-ID: <5F4EC7FA-639D-42A9-BCB6-C0477F675509@larryv.me> (raw)
In-Reply-To: <499ede49-ed95-005e-90d0-6c3265f4cea4@eastlink.ca>

> On Mar 19, 2021, at 10:40 PM, Ray Andrews <rayandrews@eastlink.ca> wrote:
> 
> As to the rest I was just stupidly forgetting that I'm in a loop.
> I'm faking a summation. We don't have summation do we?


Not that I'm aware of, but you're computing partial sums of geometric
series [*], so you have a closed-form expression available to you:

	for (( level = 1; level < 100; level++ )); do
	    ((
	        remainder = (level - 1.0) / level,
	        sum = level - level * remainder**level,
	        divided = sum * (1.0 / level)
	    ))
	    echo for level: $level, survival: $divided
	done

[*]: https://mathworld.wolfram.com/GeometricSeries.html

--
vq


      reply	other threads:[~2021-03-20  4:00 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-19 23:18 Ray Andrews
2021-03-19 23:46 ` Lawrence Velázquez
2021-03-19 23:51   ` Ray Andrews
2021-03-19 23:52 ` Oliver Kiddle
2021-03-20  2:40   ` Ray Andrews
2021-03-20  3:59     ` Lawrence Velázquez [this message]

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