[RFC PATCH v2 04/12] ipa: libipa: vector: Rename the dot product operator*() to dot()

Milan Zamazal mzamazal at redhat.com
Mon Nov 18 13:35:37 CET 2024


Laurent Pinchart <laurent.pinchart at ideasonboard.com> writes:

> The Vector class defines a set of arithmetic operators between two
> vectors or a vector and a scalar. All the operators perform element-wise
> operations, except for the operator*() that computes the dot product.
> This is inconsistent and confusing. 

I would expect it to be a dot product.  But indeed, while Emacs Calc
computes a dot product, Maxima computes a vector, so it's better to
avoid confusions.

Reviewed-by: Milan Zamazal <mzamazal at redhat.com>

> Replace the operator with a dot() function.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> ---
>  src/ipa/libipa/vector.cpp | 14 +++++++-------
>  src/ipa/libipa/vector.h   | 16 ++++++++--------
>  2 files changed, 15 insertions(+), 15 deletions(-)
>
> diff --git a/src/ipa/libipa/vector.cpp b/src/ipa/libipa/vector.cpp
> index df089f8aed9f..b2794c200b05 100644
> --- a/src/ipa/libipa/vector.cpp
> +++ b/src/ipa/libipa/vector.cpp
> @@ -85,13 +85,6 @@ namespace ipa {
>   * \return The sum of the two vectors
>   */
>  
> -/**
> - * \fn Vector::operator*(const Vector<T, Rows> &other) const
> - * \brief Compute the dot product
> - * \param[in] other The other vector
> - * \return The dot product of the two vectors
> - */
> -
>  /**
>   * \fn Vector::operator*(T factor) const
>   * \brief Multiply the vector by a scalar
> @@ -106,6 +99,13 @@ namespace ipa {
>   * \return The vector divided by \a factor
>   */
>  
> +/**
> + * \fn Vector::dot(const Vector<T, Rows> &other) const
> + * \brief Compute the dot product
> + * \param[in] other The other vector
> + * \return The dot product of the two vectors
> + */
> +
>  /**
>   * \fn T &Vector::x()
>   * \brief Convenience function to access the first element of the vector
> diff --git a/src/ipa/libipa/vector.h b/src/ipa/libipa/vector.h
> index 50e16250acfd..9dabdc28a540 100644
> --- a/src/ipa/libipa/vector.h
> +++ b/src/ipa/libipa/vector.h
> @@ -90,14 +90,6 @@ public:
>  		return ret;
>  	}
>  
> -	constexpr T operator*(const Vector<T, Rows> &other) const
> -	{
> -		T ret = 0;
> -		for (unsigned int i = 0; i < Rows; i++)
> -			ret += data_[i] * other[i];
> -		return ret;
> -	}
> -
>  	constexpr Vector<T, Rows> operator*(T factor) const
>  	{
>  		Vector<T, Rows> ret;
> @@ -114,6 +106,14 @@ public:
>  		return ret;
>  	}
>  
> +	constexpr T dot(const Vector<T, Rows> &other) const
> +	{
> +		T ret = 0;
> +		for (unsigned int i = 0; i < Rows; i++)
> +			ret += data_[i] * other[i];
> +		return ret;
> +	}
> +
>  #ifndef __DOXYGEN__
>  	template<bool Dependent = false, typename = std::enable_if_t<Dependent || Rows >= 1>>
>  #endif /* __DOXYGEN__ */



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