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cppdraft/c/math/abs.md

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+[c.math.abs]
+
+# 29 Numerics library [[numerics]](./#numerics)
+
+## 29.7 Mathematical functions for floating-point types [[c.math]](c.math#abs)
+
+### 29.7.2 Absolute values [c.math.abs]
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L9843)
+
+[*Note [1](#note-1)*:
+
+The headers [<cstdlib>](cstdlib.syn#header:%3ccstdlib%3e "17.2.2 Header <cstdlib> synopsis [cstdlib.syn]") and[<cmath>](cmath.syn#header:%3ccmath%3e "29.7.1 Header <cmath> synopsis [cmath.syn]") declare the functions described in this subclause[.](#1.sentence-1)
+
+— *end note*]
+
+[🔗](#lib:abs)
+
+`constexpr int abs(int j);
+constexpr long int abs(long int j);
+constexpr long long int abs(long long int j);
+`
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L9858)
+
+*Effects*: These
+functions have the semantics specified in the C standard library
+for the functions abs, labs, and llabs, respectively[.](#2.sentence-1)
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L9864)
+
+*Remarks*: If abs is called with an argument of type X for which is_unsigned_v<X> is true and
+if X cannot be converted to int by [integral promotion](conv.prom "7.3.7 Integral promotions [conv.prom]"), the program is ill-formed[.](#3.sentence-1)
+
+[*Note [2](#note-2)*:
+
+Allowing arguments that can be promoted to int provides compatibility with C[.](#3.sentence-2)
+
+— *end note*]
+
+[🔗](#itemdecl:2)
+
+`constexpr floating-point-type abs(floating-point-type x);
+`
+
+[4](#4)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L9881)
+
+*Returns*: The absolute value of x[.](#4.sentence-1)
+
+See also: ISO/IEC 9899:2024, 7.12.7.2, 7.22.6.1

cppdraft/c/math/fpclass.md

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+[c.math.fpclass]
+
+# 29 Numerics library [[numerics]](./#numerics)
+
+## 29.7 Mathematical functions for floating-point types [[c.math]](c.math#fpclass)
+
+### 29.7.5 Classification / comparison functions [c.math.fpclass]
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L9936)
+
+The classification / comparison functions behave the same as the C macros with the
+corresponding names defined in the C standard library[.](#1.sentence-1)
+
+See also: ISO/IEC 9899:2024, 7.12.3, 7.12.4

cppdraft/c/math/hypot3.md

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+[c.math.hypot3]
+
+# 29 Numerics library [[numerics]](./#numerics)
+
+## 29.7 Mathematical functions for floating-point types [[c.math]](c.math#hypot3)
+
+### 29.7.3 Three-dimensional hypotenuse [c.math.hypot3]
+
+[🔗](#lib:hypot,3-argument_form)
+
+`constexpr floating-point-type hypot(floating-point-type x, floating-point-type y,
+                                    floating-point-type z);
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L9897)
+
+*Returns*: √x2+y2+z2[.](#1.sentence-1)

cppdraft/c/math/lerp.md

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+[c.math.lerp]
+
+# 29 Numerics library [[numerics]](./#numerics)
+
+## 29.7 Mathematical functions for floating-point types [[c.math]](c.math#lerp)
+
+### 29.7.4 Linear interpolation [c.math.lerp]
+
+[🔗](#lib:lerp)
+
+`constexpr floating-point-type lerp(floating-point-type a, floating-point-type b,
+                                   floating-point-type t) noexcept;
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L9910)
+
+*Returns*: a+t(b−a)[.](#1.sentence-1)
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L9914)
+
+*Remarks*: Let r be the value returned[.](#2.sentence-1)
+
+If isfinite(a) && isfinite(b), then:
+
+- [(2.1)](#2.1)
+
+  If t == 0, then r == a[.](#2.1.sentence-1)
+
+- [(2.2)](#2.2)
+
+  If t == 1, then r == b[.](#2.2.sentence-1)
+
+- [(2.3)](#2.3)
+
+  If t >= 0 && t <= 1, then isfinite(r)[.](#2.3.sentence-1)
+
+- [(2.4)](#2.4)
+
+  If isfinite(t) && a == b, then r == a[.](#2.4.sentence-1)
+
+- [(2.5)](#2.5)
+
+  If isfinite(t) || !isnan(t) && b - a != 0, then !isnan(r)[.](#2.5.sentence-1)
+
+Let *CMP*(x,y) be 1 if x > y,-1 if x < y, and 0 otherwise[.](#2.sentence-3)
+
+For any t1 and t2, the product of*CMP*(lerp(a, b, t2), lerp(a, b, t1)),*CMP*(t2, t1), and*CMP*(b, a) is non-negative[.](#2.sentence-4)

cppdraft/c/math/rand.md

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+[c.math.rand]
+
+# 29 Numerics library [[numerics]](./#numerics)
+
+## 29.5 Random number generation [[rand]](rand#c.math.rand)
+
+### 29.5.10 Low-quality random number generation [c.math.rand]
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L6923)
+
+[*Note [1](#note-1)*:
+
+The header [<cstdlib>](cstdlib.syn#header:%3ccstdlib%3e "17.2.2 Header <cstdlib> synopsis [cstdlib.syn]") declares the functions described in this subclause[.](#1.sentence-1)
+
+— *end note*]
+
+[🔗](#lib:rand)
+
+`int rand();
+void srand(unsigned int seed);
+`
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L6937)
+
+*Effects*: Therand and srand functions have the semantics specified in the C standard library[.](#2.sentence-1)
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/numerics.tex#L6943)
+
+*Remarks*: The implementation
+may specify that particular library functions may callrand[.](#3.sentence-1)
+
+It is implementation-defined
+whether the rand function
+may introduce data races ([[res.on.data.races]](res.on.data.races "16.4.6.10 Data race avoidance"))[.](#3.sentence-2)
+
+[*Note [2](#note-2)*:
+
+The other random
+number generation facilities in this document ([[rand]](rand "29.5 Random number generation")) are often preferable
+to rand, because rand's underlying algorithm is unspecified[.](#3.sentence-3)
+
+Use of rand therefore continues to be non-portable, with unpredictable
+and oft-questionable quality and performance[.](#3.sentence-4)
+
+— *end note*]
+
+See also: ISO/IEC 9899:2024, 7.22.2