Calling functions that have a variable name

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Daniel Cohen on 27 Oct 2023
Commented: Daniel Cohen on 29 Oct 2023
I have a set of functions that have the general naming scheme of: function%d_%d. They all have the same input and I want to call them within two loops (for example a loop for variable n and another for k, meaning calling for functionn_k). Is it possible to do so and how?
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Stephen23 on 29 Oct 2023
"...the generated functions are named (essentially as) functionn_k."
How exactly? Are you writing them as function files (Mfiles) or as variables in the workspace or something else?
Daniel Cohen on 29 Oct 2023
I have a function that produces using MATLAB symbolic the potential function of some gravitational field. This potential can be addressed based on the order of the potential field (Look up the geopotential model in wiki, I am addressing here for example the J2 J3... fields).
And so, by having a function that computes the field potential symbolicly, I can have the function matlabFunction convert it into actual MATLAB function that are saved as Mfiles.

Matt J on 27 Oct 2023
Edited: Matt J on 27 Oct 2023
Just generate handles to all the functions. Then they can be used freely to make function calls, e.g.,
F=cellfun(@str2func, compose('function%d_%d',(1:3)',1:5), 'uni',0)
F = 3×5 cell array
{@function1_1} {@function1_2} {@function1_3} {@function1_4} {@function1_5} {@function2_1} {@function2_2} {@function2_3} {@function2_4} {@function2_5} {@function3_1} {@function3_2} {@function3_3} {@function3_4} {@function3_5}
for i=2,
for j=3,
y=F{i,j}(5)
end
end
y = 50
function y=function2_3(x)
y=10*x;
end
Walter Roberson on 27 Oct 2023
str2func is probably the best approach for this.
You could also use feval but it would not be as efficient.
Daniel Cohen on 29 Oct 2023
Thank you, str2func is exactly the solution I was looking for!

Catalytic on 27 Oct 2023
Moved: Image Analyst on 28 Oct 2023
That sounds like a bad idea. You should probably make a single function where (n,k) are one of the arguments -
function oneFunction(n,k,other_arguments)
end