Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: Moebius Newsgroups: sci.math Subject: Re: Division of two complex numbers Date: Mon, 20 Jan 2025 22:33:15 +0100 Organization: A noiseless patient Spider Lines: 38 Message-ID: References: <3OCPm1fExu73aCqhbosWeWpssJM@jntp> Reply-To: invalid@example.invalid MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Mon, 20 Jan 2025 22:33:16 +0100 (CET) Injection-Info: dont-email.me; posting-host="a448e8983be0a6b337b635e01f87c515"; logging-data="3627526"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+MZeU7FHrF2PStvwtO+p/j" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:go5XAy1YR7lGlDSqoa6SvVYlt9M= Content-Language: de-DE In-Reply-To: Bytes: 2443 Am 20.01.2025 um 21:07 schrieb Chris M. Thomasson: > On 1/20/2025 11:33 AM, Moebius wrote: >> Complex numbers can be defined as (ordered) pairs of real numbers. >> >> Then we may define (in this context): >> >>           i := (0, 1) . > > Indeed. 0+1i = (0, 1) > > In some of my vector code I allow for traditional 2-ary vector > multiplication and complex multiplication. Same in math. Even though we may use the same symbol, say "*", it denotes two different operations (in this case). > A complex number can be a simple 2-ary vector. Exactly. > [...] Multiplying two 2-ary vectors together is > different than multiply two complex number together, Right. It's the context that "decides" here; at least in math. > however they can both be stored in the same vector representation. > > z = 2 + 8i = (2, 8) > > Where 2 = Re(z), and 8 = Im(z) Right. In math we call such an object an ordered pair (or 2-tuple). See: https://en.wikipedia.org/wiki/Ordered_pair and: https://en.wikipedia.org/wiki/Tuple