以DataArrays和数组作为参数的函数

Question

我想编写一个函数，它可以在Julia中同时使用一个DataArray和一个标准的数组。实际上，我想写一个函数的方法，一个用两个类似向量的结构作为参数，另一个用两个类似矩阵的参数。

由于数组和DataArrays基本上是相同的，只是DataArray允许NA值，所以我真的不想编写每个函数的4个版本，只是为了合并数组和DataArray参数的所有不同组合。现在，我使用以下六个(!)功能，实现我的目标：

function covar_to_intensity{T<:Number}(covariates::Array{T, 1}, coefficients::Array{T, 1})
  try
    return(exp(covariates' * coefficients)[1])
  catch
    error("Multiplication of covariates and coefficients not possible.")
  end
end

function covar_to_intensity{T<:Number}(covariates::Array{T, 2}, coefficients::Array{T, 2})
  try
    return(exp(covariates * coefficients))
  catch
    error("Multiplication of covariates and coefficients not possible.")
  end
end

function covar_to_intensity{T<:Number}(covariates::DataArray{T, 1}, coefficients::DataArray{T, 1})
  try
    return(exp(covariates' * coefficients)[1])
  catch
    error("Multiplication of covariates and coefficients not possible.")
  end
end

function covar_to_intensity{T<:Number}(covariates::DataArray{T, 2}, coefficients::DataArray{T, 2})
  try
    return(exp(covariates * coefficients))
  catch
    error("Multiplication of covariates and coefficients not possible.")
  end
end

function covar_to_intensity{T<:Number}(covariates::Array{T, 1}, coefficients::DataArray{T, 1})
  try
    return(exp(covariates' * coefficients)[1])
  catch
    error("Multiplication of covariates and coefficients not possible.")
  end
end

function covar_to_intensity{T<:Number}(covariates::Array{T, 2}, coefficients::DataArray{T, 2})
  try
    return(exp(covariates * coefficients))
  catch
    error("Multiplication of covariates and coefficients not possible.")
  end
end

我知道这可能是计算这些产品的一种效率低下的方法，但对于如何编写同时使用数组和DataArrays的函数，我也很感兴趣。

谢谢!

Answer 1

通常，您可以为AbstractArray定义方法

function covar_to_intensity{T<:Number}(covariates::AbstractVector{T}, coefficients::AbstractVector{T})
  try
     return exp(covariates * coefficients)
  catch
    error("Multiplication of covariates and coefficients not possible.")
   end
end

function covar_to_intensity{T<:Number}(covariates::AbstractMatrix{T}, coefficients::AbstractMatrix{T})
  try
     return exp((covariates' * coefficients)[1])
  catch
    error("Multiplication of covariates and coefficients not possible.")
   end
end