2 Copyright Hans Dembinski 2018 - 2019.
3 Distributed under the Boost Software License, Version 1.0.
4 (See accompanying file LICENSE_1_0.txt or copy at
5 https://www.boost.org/LICENSE_1_0.txt)
8 [section:Transform Transform]
10 A [*Transform] implements a monotonic mapping between two real-valued domains, external and internal. It is used to extend the [classref boost::histogram::axis::regular regular axis]. The bins in the internal domain are of equal width, while the bins in the external domain are non-equal width. Must be [@https://en.cppreference.com/w/cpp/named_req/DefaultConstructible DefaultConstructible], [@https://en.cppreference.com/w/cpp/named_req/CopyConstructible CopyConstructible], and [@https://en.cppreference.com/w/cpp/named_req/CopyAssignable CopyAssignable].
12 [heading Required features]
14 * `T` is a type meeting the requirements of [*Transform]
15 * `t` is a value of type `T`
16 * `X` is a type with the semantics of a floating-point type
17 * `x` is a value of type `X`
18 * `Y` is a floating-point type
19 * `y` is a value of type `Y`
21 [table Valid expressions
22 [[Expression] [Returns] [Semantics, Pre/Post-conditions]]
27 Const or static member function which maps the external value to the corresponding internal value. The return type `Y` may differ from `X`.
34 Const or static member function which maps the internal value to the corresponding external value. The result of `t.inverse(t.forward(x))` must be approximately equal to `x` within floating-point precision.
41 `u` is another value of type `T`. Returns `true` if both values have the same state. Otherwise returns `false`. May be omitted if `T` is stateless. If this binary operator is not implemented, the library considers the arguments equal, if and only if their types are the same.
46 [heading Optional features]
48 * `T` is a type meeting the requirements of [*Transform]
49 * `t` is a value of type `T`
50 * `ar` is a value of an archive with Boost.Serialization semantics
52 [table Valid expressions
53 [[Expression] [Returns] [Semantics, Pre/Post-conditions]]
55 [`t.serialize(ar, n)`]
58 `ar` is a value of an archive with Boost.Serialization semantics and `n` is an unsigned integral value. Saves to the archive or loads serialized state from the archive. The version number `n` is the stored version when the object is loaded or the current version when the object is saved.
65 * [classref boost::histogram::axis::transform::id]
66 * [classref boost::histogram::axis::transform::log]
67 * [classref boost::histogram::axis::transform::sqrt]
68 * [classref boost::histogram::axis::transform::pow]