2023-04-18 17:29:19 +00:00
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import Mathlib.Data.Real.Basic
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2023-05-04 22:37:54 +00:00
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/-! # Bookshelf.Real.Basic
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A collection of basic notational conveniences.
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-/
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/--
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An abbreviation of `ℝ²` as the Cartesian product `ℝ × ℝ`.
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-/
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2023-04-18 17:29:19 +00:00
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notation "ℝ²" => ℝ × ℝ
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2023-04-22 19:11:50 +00:00
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namespace Real
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/--
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2023-05-04 22:37:54 +00:00
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Definitionally, the area of a unit circle.
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###### PORT
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As of now, this remains an `axiom`, but it should be replaced by the definition
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in `Mathlib` once ported to Lean 4.
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2023-04-22 19:11:50 +00:00
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-/
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axiom pi : ℝ
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2023-05-04 22:37:54 +00:00
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/--
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An abbreviation of `pi` as symbol `π`.
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-/
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2023-04-22 19:11:50 +00:00
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notation "π" => pi
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end Real
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