Suppose you have an array like:
double[,] rectArray = new double[10,3];
Now you want the fouth row as a double[] array of 3 elements without do
LINQ to the rescue:
var s = rectArray.Cast().Skip(9).Take(3).ToArray();
Explanation: Casting a multi-dimensional array flattens it to a single-dimensional array. After that all we need to do is skip to the element we want (the 4th element in the 2-D array resolves to Skip(9)...) and take 3 elements from it).