STD::CHI_SQUARED_DISTRIBUTION(3)

✨ std::chi_squared_distribution< _RealType > ✨

okay so bestie, this is a section-3 library manual page straight out of libstdc++, and we're talking about the iconic std::chi_squared_distribution< _RealType > — a whole random number distribution 💅. Grab a strawberry drink, we're going in.

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🎀 NAME 🎀

std::chi_squared_distribution< _RealType > — a chi_squared_distribution random number distribution. that's it, that's the name, she's serving exactly what it says on the tin 🫶

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🌸 SYNOPSIS 🌸

#include <random>

🦋 Classes 🦋

• struct param_type

⭐ Public Types ⭐

• typedef _RealType result_type

👑 Public Member Functions 👑

• chi_squared_distribution (_RealType __n) — constructor, takes the __n parameter 💖
• chi_squared_distribution (const param_type &__p) — constructor that takes a param_type instead
• template<typename _ForwardIterator, typename _UniformRandomNumberGenerator> void __generate (_ForwardIterator __f, _ForwardIterator __t, _UniformRandomNumberGenerator &__urng) — the internal generation hook, iterator-flavored
• template<typename _ForwardIterator, typename _UniformRandomNumberGenerator> void __generate (_ForwardIterator __f, _ForwardIterator __t, _UniformRandomNumberGenerator &__urng, const param_type &__p) — same iterator-flavored hook but you also hand it a param_type
• template<typename _UniformRandomNumberGenerator> void __generate (result_type *__f, result_type *__t, _UniformRandomNumberGenerator &__urng) — pointer-flavored version of the hook
• template<typename _UniformRandomNumberGenerator> void __generate (result_type *__f, result_type *__t, _UniformRandomNumberGenerator &__urng, const param_type &__p) — pointer-flavored hook plus a param_type
• result_type max () const — returns the least upper bound value of the distribution
• result_type min () const — returns the greatest lower bound value of the distribution
• _RealType n () const — hands you back the n 💫
• template<typename _UniformRandomNumberGenerator> result_type operator() (_UniformRandomNumberGenerator &__urng) — generating functions ✨
• template<typename _UniformRandomNumberGenerator> result_type operator() (_UniformRandomNumberGenerator &__urng, const param_type &__p) — generating, but with your own param_type
• param_type param () const — returns the parameter set of the distribution
• void param (const param_type &__param) — sets the parameter set of the distribution
• void reset () — resets the distribution state

🌈 Friends 🌈

• template<typename _RealType1, typename _CharT, typename _Traits> std::basic_ostream< _CharT, _Traits > & operator<< (std::basic_ostream< _CharT, _Traits > &__os, const std::chi_squared_distribution< _RealType1 > &__x) — inserts a chi_squared_distribution random number distribution __x into the output stream __os
• bool operator== (const chi_squared_distribution &__d1, const chi_squared_distribution &__d2) — return true if two Chi-squared distributions have the same parameters and the sequences that would be generated are equal
• template<typename _RealType1, typename _CharT, typename _Traits> std::basic_istream< _CharT, _Traits > & operator>> (std::basic_istream< _CharT, _Traits > &__is, std::chi_squared_distribution< _RealType1 > &__x) — extracts a chi_squared_distribution random number distribution __x from the input stream __is

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💖 Detailed Description 💖

template<typename _RealType = double>
class std::chi_squared_distribution< _RealType >"A
    chi_squared_distribution random number distribution.

(yes the stray "A up there is literally in the page, we don't ask questions, we just respect her 🙈)

The formula for the normal probability mass function is

$p(x|n) = ac{x^{(n/2) - 1}e^{-x/2}}{Gamma(n/2) 2^{n/2}}$

Since

C++11 — she's been around, she's a classic, no cap 💜

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🧚 Member Typedef Documentation 🧚

template<typename _RealType = double> typedef _RealType
    std::chi_squared_distribution< _RealType >::result_type

The type of the range of the distribution. that's the vibe, that's the whole job 🎀

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🌸 Member Function Documentation 🌸

template<typename _RealType = double> result_type
    std::chi_squared_distribution< _RealType >::max () const [inline]

Returns the least upper bound value of the distribution. the ceiling, the limit, the "that's the most you're getting" 🔥

template<typename _RealType = double> result_type
    std::chi_squared_distribution< _RealType >::min () const [inline]

Returns the greatest lower bound value of the distribution. the floor, the baseline, the starting line ⭐

template<typename _RealType = double> template<typename
    _UniformRandomNumberGenerator> result_type
    std::chi_squared_distribution< _RealType >::operator()
    (_UniformRandomNumberGenerator & __urng) [inline]

Generating functions. this is the one you actually call, bestie 💅

template<typename _RealType = double> param_type
    std::chi_squared_distribution< _RealType >::param () const [inline]

Returns the parameter set of the distribution. all the little settings, in a neat lil bundle 🎁

template<typename _RealType = double> void std::chi_squared_distribution<
    _RealType >::param (const param_type & __param) [inline]

Sets the parameter set of the distribution.

Parameters

• __param — the new parameter set of the distribution.

template<typename _RealType = double> void std::chi_squared_distribution<
    _RealType >::reset () [inline]

Resets the distribution state. fresh start, clean slate, main character reinvention energy 🌈

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💫 Friends And Related Symbol Documentation 💫

template<typename _RealType = double> template<typename _RealType1, typename
    _CharT, typename _Traits> std::basic_ostream< _CharT, _Traits > &
    operator<< (std::basic_ostream< _CharT, _Traits > & __os, const
    std::chi_squared_distribution< _RealType1 > & __x) [friend]

Inserts a chi_squared_distribution random number distribution __x into the output stream __os.

Parameters

• __os — an output stream.
• __x — a chi_squared_distribution random number distribution.

Returns

The output stream with the state of __x inserted or in an error state.

lowkey important: if things go sideways you don't get a value, you get the stream sitting in an error state. so check it, bestie 😭

template<typename _RealType = double> bool operator== (const
    chi_squared_distribution< _RealType > & __d1, const
    chi_squared_distribution< _RealType > & __d2) [friend]

Return true if two Chi-squared distributions have the same parameters and the sequences that would be generated are equal. twin flames fr fr 🫶

template<typename _RealType = double> template<typename _RealType1, typename
    _CharT, typename _Traits> std::basic_istream< _CharT, _Traits > &
    operator>> (std::basic_istream< _CharT, _Traits > & __is,
    std::chi_squared_distribution< _RealType1 > & __x) [friend]

Extracts a chi_squared_distribution random number distribution __x from the input stream __is.

Parameters

• __is — an input stream.
• __x — a chi_squared_distribution random number generator engine.

Returns

The input stream with __x extracted or in an error state.

same deal as the output side: error state is always a possibility. it's giving "read the stream state, don't assume" 💀

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🍓 Author 🍓

Generated automatically by Doxygen for libstdc++ from the source code. not a human, not a poet, just Doxygen doing her thing 💜

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and that's the whole page, periodt ✨ this one came to you courtesy of libstdc++ (that's the footer, she's the source/version, and she's iconic), auto-generated from the source code by Doxygen for the std::chi_s...RealType >(3) page — mwah, take care of her, she's your bestie now 👑💖