Vectorized way to assign columns/rows of matrix to struct array's field

Currently I'm using a for loop to assign parts of a matrix to struct's field, like this:

clear

len = 90000;
width = 51;

structArray(1:len) = struct("field",zeros(width,1));
matrixToAssign = rand(width,len);

for i=1:len
    structArray(i).field = matrixToAssign(:,i);
end

Because I could vectorize the calculations(not seen here), the assignment of the solutions in the for loop takes an equal amount of time relative to the calculation itself. Is there a way to do the assignment also in a fast vectorized way ?

The calculations I'm doing in this part of the script are depending on len. Typically for examples len>>90000 the accumulated calculations need around 3s and the accumulated assignments need around 2s (calculation and assignment are done multiple times). I have seen something like below, which tends in the right direction but isn't quite what I want to do. I have also seen transformations into cell arrays but I believe those are not faster than the loop method, but maybe I'm wrong.

[structArray.field] = deal(matrixToAssign); 

Answer 1

[Bruno Luong]

split = num2cell(matrixToAssign,1);
[structArray.field] = deal(split{;}); 

[Jonas Schütz]

As I mentioned, I have seen and tried this method, but it is around 7 seconds longer than the loop method because of the num2cell calls.

[Bruno Luong]

IMO If you care about speed, you shouldn't split your array into struct at the first place. It cost you 0 second.

[Jonas Schütz]

I guess you are right. I thought there is a faster way to do it. Perhaps I have to take that into consideration.