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== Old discussion ==
I corrected one serious error on this page. Someone should carefully check this and fix the others. <small>—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:71.179.164.101|71.179.164.101]] ([[User talk:71.179.164.101|talk]] • [[Special:Contributions/71.179.164.101|contribs]]) 15:08, 9 March 2008</small><!-- Template:Unsigned -->
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::That's exactly why I'm trying to ask for a discussion here. I handled the situation the way I did, and I'm interested in whether other editors have better ideas. [[User:Ylloh|ylloh]] ([[User talk:Ylloh|talk]]) 15:29, 22 February 2013 (UTC)
First, I want to acknowledge Ylloh for significantly improving this page. Second, I want to note that I am professor in ECE and teach graduate classes on this subject. I was drawn to this page because a student in my class was incorrectly using the term "punctured Hadamard code" based on this Wikipedia page. The "punctured Hadamard code" is a [2^k - 1, k,2^{k-1} - 1] code formed by puncturing any single bit of the Hadamard code (all are equivalent). This family is dual to the family of [2^k - 1,2^k - k - 1,3] Hamming codes, up to equivalence. For example, this reference [http://pages.cs.wisc.edu/~dieter/Courses/2013s-CS880/Scribes/PDF/lecture03.pdf] makes this point without discussing equivalence). I don't know if there is a standard term (other than 1st-order Reed-Muller) for the code this page calls the "punctured Hadamard code". Using standard terminology, however, it should be called the "augmented Hadamard code" because augmenting refers to increasing the dimension by one whereas puncturing refers to reducing the length by 1. Thus, I am going fix this on the main page. <!-- Template:Unsigned --><small class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Hpfister|Hpfister]] ([[User talk:Hpfister#top|talk]] • [[Special:Contributions/Hpfister|contribs]]) 15:48, 15 September 2019 (UTC)</small> <!--Autosigned by SineBot-->
== External links modified ==
Hello fellow Wikipedians,
I have just modified one external link on [[Hadamard code]]. Please take a moment to review [https://en.wikipedia.org/w/index.php?diff=prev&oldid=807408345 my edit]. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit [[User:Cyberpower678/FaQs#InternetArchiveBot|this simple FaQ]] for additional information. I made the following changes:
*Added archive https://web.archive.org/web/20110720084646/http://www.complextoreal.com/CDMA.pdf to http://www.complextoreal.com/CDMA.pdf
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== Not an inner product ==
The nondegenerate bilinear form defined in the article is not an inner product. Taking x = 1 yields a counterexample to the positive definiteness. <!-- Template:Unsigned --><small class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Ntheazk|Ntheazk]] ([[User talk:Ntheazk#top|talk]] • [[Special:Contributions/Ntheazk|contribs]]) 16:37, 20 March 2020 (UTC)</small> <!--Autosigned by SineBot-->
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