MATLAB: Define Matrix array as a function

matrix array

Hi everybody.
Would you please guide me how to define an array of a Matrix as a function? For example how can array or components of a Matrix be a Sinc function?
Thanks in advance.

Best Answer

In basic MATLAB, the closest you can get is to have a cell array of function handles that you would have to access and apply to the inputs. (Or, I suppose, an array of some kind of object oriented objects that you created yourself for this purpose.)
In the Symbolic Toolbox, each element of a symbolic array can be used to store a symbol that is a symbolic function. For example,
syms y(t)
A(t) = [sin(t), sinc(t), y]
A(pi/4)
ans = 
[ 2^(1/2)/2, (4*sin(pi^2/4))/pi^2, y(pi/4)]
However, this formation is more
A = symfun([sin(t), sinc(t), y], t)
so you will see that A(t) = [ sin(t), sin(pi*t)/(t*pi), y(t)] where sinc(t) has been evaluated already instead of remaining as an unresolved function call.
If you were to instead use
A = [sin(t), sinc(t), y]
then although you would still see A = [ sin(t), sin(pi*t)/(t*pi), y(t)] looking exactly the same content, the result would not be a symbolic function, and attempting A(pi/2) for example would get you a subscript error.
It is not possible to construct a numeric array in which some of the entries are "macros" like in Excel such that changing other entries in the array would change the calculated result at that location.
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