Calling user functions recursively

I have user created functions called f11(), f12(), f13(), f21(), f22(), f23()... I want to call these function recursively for i=1 to n for j=j to m eval(fij()) I have tried with the eval() function. It does not work. Could someone help me? thank you

[John D'Errico]

And yet another reason not to write numbered functions, numbered variables, etc. Regardless, you are asking to call them in sequence, but not recursively. A recursive call is one where a function calls itself.

Answer 1

[dbmn]

First of all: Listen to John - he is right about this. Try not to use numbered functions and variables (you can read why this is a bad idea on numerous posts on Matlab Answers - just search).

But because I know you gonna try it anyway, here is a solution

A) Do nothing but change your eval to: (BAD)

eval(sprintf('f%d%d()', i, j))

B) Create a function caller that handles your functions (Better, but uses still the numbered functions - but at least it can be debugged)

function [] = function_caller(idx)
switch idx
  case 1
      % your function here
  case 2
      % your function here
end
end

C) Rewrite your code and avoid the numbered functions - there must be a smarter way to do this.

Work with Functions and Subfunctions instead and try to get a clear image about what your code actually needs to do in what order.

[Isabelle Armanville]

Thank you!

Answer 2

[Stephen23]

Why not just put the functions into a cell array, then this is trivial:

 >> C = {@rand,@()randi(9,1),@()randi([10,20],1)};
 >> cellfun(@(f)f(),C)
 ans =
      0.91338            6           11

or

 for k = 1:numel(C)
     C{k}()
 end

Calling numbered functions is not a good solution:

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval