I need to convert the following collection into double[,]:
var ret = new List<double[]>();
All the arrays in the list have the same length. The simplest approach, ret.ToArray()
, produces double[][], which is not what I want. Of course, I can create a new array manually, and copy numbers over in a loop, but is there a more elegant way?
Edit: my library is invoked from a different language, Mathematica, which has not been developed in .Net. I don't think that language can utilize jagged arrays. I do have to return a multidimensional array.
I don't believe there's anything built into the framework to do this - even Array.Copy
fails in this case. However, it's easy to write the code to do it by looping:
using System;
using System.Collections.Generic;
class Test
{
static void Main()
{
List<int[]> list = new List<int[]>
{
new[] { 1, 2, 3 },
new[] { 4, 5, 6 },
};
int[,] array = CreateRectangularArray(list);
foreach (int x in array)
{
Console.WriteLine(x); // 1, 2, 3, 4, 5, 6
}
Console.WriteLine(array[1, 2]); // 6
}
static T[,] CreateRectangularArray<T>(IList<T[]> arrays)
{
// TODO: Validation and special-casing for arrays.Count == 0
int minorLength = arrays[0].Length;
T[,] ret = new T[arrays.Count, minorLength];
for (int i = 0; i < arrays.Count; i++)
{
var array = arrays[i];
if (array.Length != minorLength)
{
throw new ArgumentException
("All arrays must be the same length");
}
for (int j = 0; j < minorLength; j++)
{
ret[i, j] = array[j];
}
}
return ret;
}
}