How to pop the content of a matrix in a way like pop the content of a cell

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We know that the arguments of a function can be placed in a cell and call it like this:
aCell = {arg1,arg2,arg3};
myFunction(aCell{:});
Is there a way to do this for a vector instead?
I tried this way, but it does not work
aVector = [2 3 4 5];
myFun(aVector(:)) % this does not work, the argument is a column vector [2;3;4;5] instead.
Similarly,
aVec = [1 2 3];
aCell = {'d','dew',aVec(:)} % I would expect aCell is {'d','dew',1,2,3}, but it is {'d','dew',[1;2;3]},
Thanks.
  2 Comments
Stephen23
Stephen23 on 19 Jun 2020
Edited: Stephen23 on 19 Jun 2020
There is no way to do this with a numeric array (or a char array, logical array, etc.). The only ways to generate a comma-separated list (the proper name for what you are trying to do) are from a cell array or from a field of a structure:

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Accepted Answer

Ameer Hamza
Ameer Hamza on 19 Jun 2020
Madhan's answer already shows how to use num2cell. Following just show how can you avoid the creation of a temporary variable
v = [1 2 3];
myFun(struct('a', num2cell(v)).a)
  3 Comments
Ameer Hamza
Ameer Hamza on 19 Jun 2020
Timing will be higher because of the additional overhead of struct creation (num2cell() being equivalent in both cases). However, it is only a concern if the function myFun() is itself has very small execution time (in order of microseconds) or the number of input arguments is in millions. If timing is a primary considerations, then it will be faster to just take input as an array rather than splitting it into an argument list. The point about obfuscation seems valid.

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More Answers (2)

madhan ravi
madhan ravi on 19 Jun 2020
Edited: madhan ravi on 19 Jun 2020
aVector = [2 3 4 5];
aVector = num2cell(aVector);
myFun(aVector{:}) % ;)

Walter Roberson
Walter Roberson on 19 Jun 2020
No there is not.
You can num2cell the vector and assign that to a variable and do expansion on that.
There are ways to use auxiliary anonymous functions to do the num2cell for you, and even to do cell expansion on the result, but when you proceed that way, the MATLAB parser will not know that multiple outputs are required and will pull out only the first value.

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