Variables number of for loops using recursion

Hello,

I have been thinking to do this for a while, and have been searching here and there and no results.

Lets say the input=recursion(d,f) , where each of d and f is a vector of n.

I want the function code to do exactly as:

 for i=1:f(1)
  for i2=1:f(2)
   for i3=1:f(3)
   .......
   .......
     for in=1:f(n)
       _do something such as calling other function to run other software        program in  background_
        d=d+[0,0,...,1]
     end
   .......
   .......
    d=d+[0,0,1....]
   end
   d=d+[0,1,0....]
  end
  d=d+[1,0,0,....]
end

I think the only way to do this is through recursion, and somehow I prefer that way, because I need to learn it also how to do recursion properly.

Please advise how to do this.

Answer 1

[James Tursa]

Does this do what you want (assumes all of the f values are positive integers):

function forloops(d,f)
n = ones(1,numel(f)+1); % Index vector (first one is a dummy for programming purposes)
F = [2 f(:)']; % Index limit vector (first one is a dummy for programming purposes)
D = [0 d(:)']; % d vector (first one is a dummy for programming purposes)
while( true )
    % Do your stuff here
    % Equivalent for-loop indexes are in n(2:end)
    % Equivalent d vector is in D(2:end)
    n(end) = n(end) + 1; % Increment "inner" index
    D(end) = D(end) + 1; % Increment "inner" d vector spot
    k = n > F;
    while( any( k ) ) % Loop to cycle any indexes that are over limit
        x = find(k,1); % Find the one that just went over the limit
        n(x) = 1;  % Set the one that is over the limit back to 1 ...
        n(x-1) = n(x-1) + 1; % ... and increment the immediate "outer" loop index
        D(x-1) = D(x-1) + 1; % Also increment the related "outer" d vector spot
        k = n > F; % Check to see if the "outer" one went over the limit
    end
    if( n(1) == 2 ) % If 1st dummy index is 2, we are done
        break;
    end
end
end