I want matlab to read my input data(txt file)

this is my input data

I want matlab to read my input data in the beginning of the code.

If i run this code, comes out;

Undefined function or variable 'gettrussdata2D'.

Error in Trussd (line 2)

[nodes,elems,C,A,bcs,loads] = gettrussdata2D(filename);

filename = uigetfile('*.txt','Select the input file');
[nodes,elems,C,A,bcs,loads] = gettrussdata2D(filename);
Nel = size(elems,1);
Nnodes = size(nodes,1);

alldofs = 1:2*nodeNumber;
K = zeros(2*nodeNumber);
u = zeros(2*nodeNumber,1);
f = zeros(2*nodeNumber,1);

dofspec = [];
for ii = 1:size(bcs,1)
    thisdof = 2*(bcs(ii,1)-1)+bcs(ii,2);
    dofspec = [dofspec thisdof];
    u(thisdof) = bcs(ii,3);
end

doffree = alldofs;
doffree(dofspec) = [];

for ii = 1:size(loads,1)
    f(2*(loads(ii,1)-1)+loads(ii,2)) = loads(ii,3);
end

for iel = 1:Nel
    elnodes = elems(iel,1:2);
    nodexy = nodes(elnodes, :);
    [Kel] = TrussElement2D(nodexy,C(iel),A(iel));
    
    eldofs = 2*(elnods(1)-1)+1:2*(elnodes(1)-1)+2;
    eldofs = [dleofs 2*(elnodes(2)-1)+1:2*(elnodes(2)-1)+2];
    K(eldofs,eldofs) = K(eldofs,eldofs) +Kel;
end

u(doffree) = K(doffree,doffree)\(f(doffree)-K(doffree,dofspec)*u(dofspec));
f(dofspec) = K(dofspec,:)*u;
format long
disp(['Displacement vector:']);u
disp(['Forcevector:']);f

[Rik]

And here is a classmate who also forgot to explain where the gettrussdata2D function should be comming from. It isn't part of Matlab, nor are there any other results on Google. The TrussElement2D is also a mystery.

Have a read here. It will greatly improve your chances of getting an answer.

[KSSV]

Attach your file ...not a image. Tell us wht you want to extract from there.