Not enough input arguments in Matlab R2021b

function [K] = assembly_gl(Ke,gdl_bar,K)

%--Function that assembles the global stiffness matrix for the entire structure

%Ke=Enter the name of the finite element stiffness matrix you want to add

%gdl_bar=Vector containing the degrees of freedom of the finite element

%K=Specify the array in which the assembly will be stored

for igdl=1:4

ifila = gdl_bar(igdl);

for jgdl=1:4

jcolumna = gdl_bar(jgdl);

K(ifila,jcolumna) = K(ifila,jcolumna) + Ke(igdl,jgdl);

end

end

end

%I don't understand why the error comes out: Not enough input arguments.

%I have already entered all the arguments

%Please help me, thank you so much

[Chunru]

The code above defined the function. How do you call it?

[Pedro Rodriguez]

I saved the script as: untitled.m

Just in case, it is used to assemble, that is, join more than one matrix into a single matrix, so this code should be:

%DOFT=Degrees of freedom of the entire structure

%For example: DOFT=10

K = zeros(size(DOFT))

However I would use this code: K = zeros(size(DOFT)) in the script that executes the function:assembly_gl(Ke,gdl_bar,K)

My goal is to execute the function:assembly_gl(Ke,gdl_bar,K) many times with a for loop, however I just need the function to be able to execute:assembly_gl(Ke,gdl_bar,K) in a .m file

The problem is that I can't run: untitled.m, due to the error: Not enough input arguments, Error in untitled (line 7)

Answer 1

[VBBV]

Ke = randi(4,4);  % assume this as FE stiffness matrix to be added
gdl_bar = [2 2 4 4];  % no of DOF for each element in stiffness 
K = zeros(size(Ke)); % pre-allocate matrix to store assembly 
K = assembly_gl(Ke,gdl_bar,K)  % resulting assembled matrix you want 

K = 4×4

0 0 0 0 0 9 0 13 0 0 0 0 0 8 0 11

function [K] = assembly_gl(Ke,gdl_bar,K)
%--Function that assembles the global stiffness matrix for the entire structure
%Ke=Enter the name of the finite element stiffness matrix you want to add
%gdl_bar=Vector containing the degrees of freedom of the finite element
%K=Specify the array in which the assembly will be stored
for igdl=1:4
    ifila = gdl_bar(igdl);
    for jgdl=1:4
        jcolumna = gdl_bar(jgdl);
        K(ifila,jcolumna) = K(ifila,jcolumna) + Ke(igdl,jgdl);
    end
end
end

give input matrix parameters to the function and pre-allocate any matrix used as argument in function

[Pedro Rodriguez]

I saved the script as: untitled.m

And I still have this error: Error in untitled (line 7)

Line 7 = ifila = gdl_bar(igdl);

I even tried running it in Matlab Online

[Torsten]

As you can see, the above code was run in MATLAB Online.

So it seems that something is not correct with your inputs to the function.

[Pedro Rodriguez]

I have managed to clarify my doubts, thank you very much to VBBV