Talk:Dc (computer program)

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I have been unable to find any libraries of functions for 'dc' (e.g., log, sin, etc). If someone finds some, please add external links.

Wouldn't it be better to use an example that actually works? Because when I type
12 3 4 ^ + _11 / v 22 -
I get
dc: square root of negative number

You miss-typed the example, the correct one is
12 _3 4 ^ + 11 / v 22 -
After command p you get
-20 Annie Yousar (talk) 14:14, 15 March 2025 (UTC)[reply]

Can someone explain how the following works?
[q]sa[ln0=aln80~Psnlbx]16isb572CCB9AE9DB03273snlbxq

It encodes the email address in the hex constant n=0x572CCB9AE9DB03273 and operates on it with the macro b defined as [ln0=aln80~Psnlbx]. This recursively calls itself until n is equal to zero. -- Autopilot (talk) 22:44, 15 May 2010 (UTC)[reply]

Just did a small optimization (in code length) to it: [q]sa[d0=a80~anlbx]16isb572CCB9AE9DB03273lbxq. Could anyone help writing another dc code to generate that hexadecimal number? I think it will be a good idea to add them, in pair, as an example of string handling in dc which is not yet covered by other examples. Billyauhk (talk) 08:08, 26 July 2011 (UTC)[reply]

: Sorry but I forgotten that we cannot construct a string in dc...but I have just figured out the way to construct the constant: (echo -n "0123456789" | xxd -p -u -c 1; echo 0) | dc -"16i0[80?d0!=x*+]dsxx10op" (for Bash...and using GNU dc where != is accepted). For the string "Wikipedia", the constant is: 30E9C997869D7A6B80 Billyauhk (talk) 10:51, 26 July 2011 (UTC)[reply]

Billyaukh missed the "e" in dc -e "16i0[80?d0!=x*+]dsxx10op" Annie Yousar (talk) 11:46, 2 February 2025 (UTC)[reply]

The current text says:

"It is one of the oldest Unix utilities, predating even the invention of the C programming language"

I believe that this is slightly incomplete. Wouldn't it be better to specify the original implementation language, rather than giving a hint at which one it is not? --Blazar.writeto() 14:39, 2 August 2008 (UTC)[reply]

A dc prototype for PDP-7 Unix was written in B. [1][2] Dc was written in assembly in V6. [3] It was rewritten in C for V7. [4] The Plan 9 version is essentially the same as the V7 version with a few small changes to accommodate the new C compiler. 70.225.161.132 (talk) 06:27, 27 March 2011 (UTC)[reply]

There is a typo (or rather, a grammar mistake) in the article's "Input/Output" section: It says "... will affect the parsing of the every numeric value ..."—in my opinion, the second "the" is wrong, but I cannot change it myself as the article is protected. Would some registered user correct this, please?--131.152.224.31 (talk) 14:33, 29 September 2011 (UTC)[reply]

Oops, obviously, it is not protected. I'm gonna change it myself. Cheers!--131.152.224.31 (talk) 14:34, 29 September 2011 (UTC)[reply]

A commented version is slightly easier to understand ...

This example, Perl source containing embedded dc source, was formatted with language-specific, syntax-aware color coding. While I personally find that the jarring color shifts make source code almost unreadable, I would have left this style in place were it not already meaningless:

1. The Wikipedia renderer doesn't have a style for “dc” source at all.
2. The renderer doesn't handle nested source.
3. The renderer doesn't handle multiple languages in one block of code.
4. All the dc source, which (in this article on dc) is the whole point of the example, was rendered in one uniform color as being a single Perl function argument.

Since the colors only distracted from the dc example by highlighting the Perl code, I'm dropping those colors, leaving the dc and Perl source unchanged. 206.205.52.162 (talk) 16:50, 19 April 2013 (UTC)[reply]

Some more examples of bad coloring needed attention. Editors, in this article about dc, it isn't clearly an improvement to try to color-code dc source using the Perl style, or the bash style, or any other unrelated style. 50.181.30.121 (talk) 23:54, 24 April 2014 (UTC)[reply]

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(named) Register = Stack of Arrays

So I can access a named register's TOS array via ":" and ";". This is fine. But I've an idea for something to code which massively would benefit if I could access the default register in the same way. So does it have a hidden name?

I'll read the source, if my impatience wins over my patience ... 2003:DD:6F34:8975:F4A0:F975:5A7:A98E (talk) 12:33, 16 February 2025 (UTC)[reply]

I believe that this article is copied almost verbatim from its sources, since the language used is far too technical for the general public. Although I have fixed some language, there are other instances that I have not corrected. Please assist me in polishing this article. ZImperator (talk) 03:34, 21 November 2025 (UTC)[reply]

Most people don't understand wikipedia articles, at least not fully. A cry out to dumb down articles is contra productive, because it robs more knowledgeable users from insights. Any actual improvements in clarity is of course to be applauded. ~2026-55951-0 (talk) 13:36, 5 February 2026 (UTC)[reply]

It's not about dumbing down the article, it's about it making it at least somewhat readable. Wikipedia is a general purpose encyclopedia, not a technical guide. The article contains a lot of things you'd typically see in a man page (manual) for the command. Most people should be able to understand, or be able to understand by clicking hyperlinks, every Wikipedia article. If a knowledgeable user wanted more insight into the command, they would go onto a technical site, not Wikipedia. Like I have said, Wikipedia is a general purpose encyclopedia, where everyone should have free access to the sum of human knowledge. That includes people being able to understand, at least at a surface level, such knowledge. ZImperator (talk) (contrib) 16:03, 5 February 2026 (UTC)[reply]

As an addition, see WP:TECHNICAL. Pretty much sums up my point here. ZImperator (talk) (contrib) 16:05, 5 February 2026 (UTC)[reply]