From: "Lawrence Velázquez" <vq@larryv.me>
To: Emanuel Berg <embe8573@student.uu.se>
Cc: zsh-workers@zsh.org
Subject: Re: why do ceil/floor give the decimal dot?
Date: Wed, 13 May 2015 23:53:53 -0400 [thread overview]
Message-ID: <B6914C0C-15CA-4FE2-A21A-4320D4CD4927@larryv.me> (raw)
In-Reply-To: <87d223et0a.fsf@debian.uxu>
On May 13, 2015, at 11:29 PM, Emanuel Berg <embe8573@student.uu.se> wrote:
> Take a look at this [1] zsh:
>
> prefix-len () {
> local hosts=$1
> echo $(( 32 - int(ceil(log($hosts)/log(2))) ))
> }
>
> without the integer conversion, the output for
>
> prefix-len 30
>
> isn't 27, but "27."
Yes, this is expected and correct. From "ARITHMETIC EVALUATION" in the
zshmisc(1) man page:
Promotion of integer to floating point values is performed where
necessary.
So:
- "ceil(log(30)/log(2))" returns floating-point "5."
- integer "32" is promoted to floating point "32."
- floating point "32." - floating point "5." = floating-point "27."
vq
next prev parent reply other threads:[~2015-05-14 4:02 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-14 0:32 Emanuel Berg
2015-05-14 2:56 ` Bart Schaefer
2015-05-14 3:29 ` Emanuel Berg
2015-05-14 3:53 ` Lawrence Velázquez [this message]
2015-05-14 9:53 ` Peter Stephenson
2015-05-14 21:38 ` Emanuel Berg
2015-05-14 22:14 ` Lawrence Velázquez
2015-05-14 23:29 ` Emanuel Berg
2015-05-15 0:46 ` Oliver Kiddle
2015-05-15 1:07 ` Emanuel Berg
2015-05-15 1:27 ` Bart Schaefer
2015-05-18 8:16 ` Vincent Lefevre
2015-05-14 4:04 ` Bart Schaefer
2015-05-14 9:12 ` Emanuel Berg
2015-05-14 17:54 ` Bart Schaefer
2015-05-18 8:39 ` Vincent Lefevre
2015-05-18 9:41 ` Mikael Magnusson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=B6914C0C-15CA-4FE2-A21A-4320D4CD4927@larryv.me \
--to=vq@larryv.me \
--cc=embe8573@student.uu.se \
--cc=zsh-workers@zsh.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://git.vuxu.org/mirror/zsh/
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).