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Dedekind 0.0.0
A structuralist C++23 Module Library
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The exact discrete COSINE \(\cos_N(k) = \cos(2\pi k/N) =
\Re\,\zeta_N^k\) over the Modular<N> angle — the EVEN part of the de Moivre character (= the \(\tfrac12(I+U)\) projection's real value).
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Public Types | |
| using | Domain = dedekind::morphologies::Modular<N> |
| using | Codomain = QuadraticReal<2> |
Public Member Functions | |
| constexpr QuadraticReal< 2 > | operator() (Domain k) const |
The exact discrete COSINE \(\cos_N(k) = \cos(2\pi k/N) =
\Re\,\zeta_N^k\) over the Modular<N> angle — the EVEN part of the de Moivre character (= the \(\tfrac12(I+U)\) projection's real value).
NOT a new trig table: it is literally Re of character<N>(1) resolved. An IsArrow Modular<N> → ℝ, EXACT where the character resolves (N=8, in ℚ(√2)). With DiscreteSin it gives Euler's formula exactly: \(\zeta_N^k = \cos_N(k) + i\,\sin_N(k)\).