How to get the values in the array and use it for user input, then creating an array for the inputs?

I have an array=(5 6 8) how can i ask an input for f(5),f(6),f(8) and put all inputs in an array

Answer 1

[Parag Jhunjhunwala]

The below code asks the user to enter the values for f(5), f(6) and f(8) and inserts the user input in the vector f at the respective positions(i.e. 5,6, and 8):

arr=[5 6 8];
for i=1:length(arr)
    prompt = ['f(' num2str(arr(i)) '):'];
    f(arr(i)) = input(prompt);
end

[michael]

thanks! but it seems like it doesn't support a negative index any way to make it possible?

[Parag Jhunjhunwala]

MATLAB only supports positive indices. So, I think it's not possible.

[Stephen23]

"but it seems like it doesn't support a negative index any way to make it possible? "

You are confusing data with code. Better to keep them separate and iterate over indices, not over (meta-)data:

X = [5,6,8];
Y = nan(size(X));
for k = 1:numel(X)
    Y(k) = input("f("+k+")");
end

More robust would be to use INPUT's 's' option and STR2DOUBLE.