choose multiple functions from a larger group

I've 7 function, i want to be able to choose several of them, I know with if and swich i can pick only one of these seven, i need something that allows me to select, for example, 4 function of these functions from the main group.

[dpb]

Indexing expression into an array of function handles???

[Walter Roberson]

Yes, cell array of function handles. randperm(7, 4) to select random indices.

Answer 1

[Image Analyst]

How about this:

numFunctionsToCall = 4;
randomNumbers = randi(7, numFunctionsToCall, 1)
for k = 1 : numFunctionsToCall
    thisNumber = randomNumbers(k);
    if thisNumber == 1
        results = function1();
    elseif thisNumber == 2
        results = function2();
    elseif thisNumber == 3
        results = function3();
    elseif thisNumber == 4
        results = function4();
    elseif thisNumber == 5
        results = function5();
    elseif thisNumber == 6
        results = function6();
    elseif thisNumber == 7
        results = function7();
    end
end

If not, then explain better how you want it to operate.

[simone zappalà]

i think with this i just take randomly four of the seven functions, i need to decides which one i want to choose.

Anyway thx for answer.

[Image Analyst]

Then just assign the ones you want to use, or ask the user for them with input() or some drop down lists.

functionsToCall = [6,3,4,1]; % Define which functions are to be called, in the order they are to be called.
for k = 1 : length(functionsToCall)
    thisNumber = functionsToCall(k);
    if thisNumber == 1
        results = function1();
    elseif thisNumber == 2
        results = function2();
    elseif thisNumber == 3
        results = function3();
    elseif thisNumber == 4
        results = function4();
    elseif thisNumber == 5
        results = function5();
    elseif thisNumber == 6
        results = function6();
    elseif thisNumber == 7
        results = function7();
    end
end

Answer 2

[dpb]

Using listdlg would be one easy-to-code way to get started -- although it doesn't have the facility to limit the number selected in 'MultiSelect' mode.

You could put it in a loop and repeat with the list not containing the already selected values until four were selected with single selection only.

Or you could throw away more than four if user got overly exuberant in multiple selections -- of course, then it's again somewhat arbitrary about which one you keep/don't.

If we had any idea of what the end purpose here were to be, might be easier to make more specific recommendations...

Answer 3

[Walter Roberson]

functions_to_pick_from = {@first, @second, @third, @fourth, @fifth, @sixth, @seventh};

num_to_pick = 4;
num_to_pick_from = length(functions_to_pick_from);
random_indices = randperm(num_to_pick_from, num_to_pick);

random_handles = functions_to_pick_from(random_indices);

for K = 1 : num_to_pick
    results{K} = random_handles{K}(x);  %run the function on appropriate input
end

[Image Analyst]

She didn't want random: "i think with this i just take randomly four of the seven functions, i need to decides which one i want to choose." So maybe, or maybe not, she has a way to decide on the 4 functions to choose from, and their order, like an edit field on a GUI or a call to the input function.

[dpb]

But since she didn't provide any klews as to what, specifically, she did/does want, I think Walter just used randperm to illustrate picking a set of four function handles from the function handle array and how to use those -- it's up to OP to decide the "how".