std::chi_squared_distribution

 

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std::chi_squared_distribution

Member functions

chi_squared_distribution::chi_squared_distribution

chi_squared_distribution::reset

Generation

chi_squared_distribution::operator()

Characteristics

chi_squared_distribution::n

chi_squared_distribution::param

chi_squared_distribution::min

chi_squared_distribution::max

Non-member functions

operator==operator!= (C++11)(C++11)(until C++20)

operator<<operator>> (C++11)(C++11)

 

Defined in header <random>
template< class RealType = double > class chi_squared_distribution;		(since C++11)

The chi_squared_distribution produces random numbers x>0 according to the Chi-squared distribution:

f(x;n) =

x(n/2)-1 e-x/2

Γ(n/2) 2n/2

Γ is the Gamma function (See also std::tgamma) and n are the degrees of freedom (default 1).

Member types

Member type	Definition
result_type	RealType
param_type	the type of the parameter set, unspecified

Member functions

Template:cpp/numeric/random/distribution/dcl list constructorTemplate:cpp/numeric/random/distribution/dcl list resetTemplate:cpp/numeric/random/distribution/dcl list operator()Template:cpp/numeric/random/chi squared distribution/dcl list nTemplate:cpp/numeric/random/distribution/dcl list paramTemplate:cpp/numeric/random/distribution/dcl list minTemplate:cpp/numeric/random/distribution/dcl list max

Generation

Characteristics

Non-member functions

Template:cpp/numeric/random/distribution/dcl list operator cmpTemplate:cpp/numeric/random/distribution/dcl list operator ltltgtgt

External links

• Weisstein, Eric W. "Chi-Squared Distribution." From MathWorld--A Wolfram Web Resource.
• Chi-squared distribution. From Wikipedia.