plssvm::operators Namespace Reference

Namespace containing operator overloads for std::vector and other mathematical functions on vectors. More...

Classes
struct	transposed
	Wrapper struct for overloading the dot product operator. More...

Functions
template<typename T >
	transposed (const std::vector< T > &) -> transposed< T >
	Deduction guide for the plssvm::operators::transposed struct needed for C++17.
template<typename T >
T	operator* (const transposed< T > &lhs, const std::vector< T > &rhs)
	Calculate the dot product ( \(x^T \cdot y\)) between both std::vector. More...
template<typename T >
T	dot (const std::vector< T > &lhs, const std::vector< T > &rhs)
	Calculate the dot product ( \(x^T \cdot y\)) between both std::vector. More...
template<typename T >
T	sum (const std::vector< T > &vec)
	Accumulate all elements in the std::vector vec. More...
template<typename T >
T	squared_euclidean_dist (const std::vector< T > &lhs, const std::vector< T > &rhs)
	Calculates the squared Euclidean distance of both vectors: \(d^2(x, y) = (x_1 - y_1)^2 + (x_2 - y_2)^2 + \dots + (x_n - y_n)^2\). More...
template<typename T >
constexpr T	sign (const T x)
	Returns +1 if x is positive and -1 if x is negative or 0. More...

Detailed Description

Namespace containing operator overloads for std::vector and other mathematical functions on vectors.

Function Documentation

operator*()

template<typename T >

T plssvm::operators::operator* ( const transposed< T > &  lhs, const std::vector< T > &  rhs  )

inline

Calculate the dot product ( \(x^T \cdot y\)) between both std::vector.

Explicitly uses std::fma for better performance and accuracy.

Template Parameters

T	the value type

Parameters

[in]	lhs	the first vector
[in]	rhs	the second vector

Returns

the dot product ([[nodiscard]])

dot()

template<typename T >

T plssvm::operators::dot ( const std::vector< T > &  lhs, const std::vector< T > &  rhs  )

inline

Calculate the dot product ( \(x^T \cdot y\)) between both std::vector.

Explicitly uses std::fma for better performance and accuracy.

Template Parameters

T	the value type

Parameters

[in]	lhs	the first vector
[in]	rhs	the second vector

Returns

the dot product ([[nodiscard]])

sum()

template<typename T >

T plssvm::operators::sum ( const std::vector< T > &  vec )

inline

Accumulate all elements in the std::vector vec.

Uses OpenMP SIMD reduction to speedup the calculation.

Template Parameters

T	the value type

Parameters

[in]

vec

the elements to accumulate

Returns

the sum of all elements ([[nodiscard]])

squared_euclidean_dist()

template<typename T >

T plssvm::operators::squared_euclidean_dist ( const std::vector< T > &  lhs, const std::vector< T > &  rhs  )

inline

Calculates the squared Euclidean distance of both vectors: \(d^2(x, y) = (x_1 - y_1)^2 + (x_2 - y_2)^2 + \dots + (x_n - y_n)^2\).

Explicitly uses std::fma for better performance and accuracy.

Template Parameters

T	the value type

Parameters

[in]	lhs	the first vector
[in]	rhs	the second vector

Returns

the squared euclidean distance ([[nodiscard]])

sign()

template<typename T >

constexpr T plssvm::operators::sign ( const T  x )

inlineconstexpr

Returns +1 if x is positive and -1 if x is negative or 0.

Parameters

[in]

x

the value to calculate the sign for

Returns

+1 if x is positive and -1 if x is negative or 0 ([[nodiscard]])