How to assign different values to different variables at once using deal() function?

I had some values which are in a single vector named "param". Let us consider it has "n" elements. I want to assign this "n" values to "n" different variables. I'm using deal() function to do this, but I'm not getting the results as I expected.

[a1,a2,a3,..........., an] = deal(param)

I want values to be assigned in this way

a1 = param(1); a2 = param(2) .... , an = param(n)

can someone help me in this regard?

param = [1 2 3 4 5];
[a1,a2,a3,a4,a5] = deal(param)

a1 = 1×5

1 2 3 4 5

a2 = 1×5

1 2 3 4 5

a3 = 1×5

1 2 3 4 5

a4 = 1×5

1 2 3 4 5

a5 = 1×5

1 2 3 4 5

[Nikhil]

[B1,...,Bn] = deal(A) copies the single input argument A and returns it as the output arguments B1,...,Bn. It is the same as B1 = A, …, Bn = A. In this syntax, you can specify an arbitrary number of output arguments.

That's why the array param is getting assigned to a1,a2,..,a5.

[Dyuman Joshi]

Any particular reason why you want to do this assignment?

[Steven Lord]

Can you dynamically create variables with numbered names like x1, x2, x3, etc.? Yes.

Should you do this? The general consensus is no. That Answers post explains why this is generally discouraged and offers several alternative approaches.

If the vector you were trying to assign to those variables had 1000, 10000, or more elements do you really want 1000, 10000, or more individual variables in the workspace? Probably not. Instead of assigning to and using (for example) a523 why not just use param(523)?

Answer 1

[Jacob Mathew]

Hi Jagadeesh,

The deal function is used to distribute a single input into multiple outputs or multiple inputs into multiple outputs where the number of input and outputs are equal. However the documentation does recommend to use other approaches when possible.

With respect to your query, it is natively not possible to distribute the param variable as you intended. To achieve your desired behaviour, we have to manually convert the param array into a cell array:

param = [1 2 3 4 5];
cellParam = num2cell(param);
[a1,a2,a3,a4,a5] = deal(cellParam{:});
a1

a1 = 1

a2

a2 = 2

a3

a3 = 3

a4

a4 = 4

a5

a5 = 5

[Stephen23]

https://www.mathworks.com/help/matlab/matlab_prog/comma-separated-lists.html

https://www.mathworks.com/matlabcentral/answers/1656435-tutorial-comma-separated-lists-and-how-to-use-them

[michal.markun]

I noticed that

[a1,a2,a3,a4,a5] = cellParam{:}

has the same effect (Matlab R2024b).