slp method to minimize function

Error:

Error using SLP>f_SLPclass (line 26)

x should be 5 elements long, but instead it is length 2

Error in SLP (line 6)

[f,g]=f_SLPclass(x);

clear;
clc;
x=[0;10];
Tolx=0.01;
TolCon=0.01;
[f,g]=f_SLPclass(x);    
[gradf,gradg]=g_SLPclass(x);
coverged=false;
iter=0;
while converged 
    c=gradf';
    a=gradg';
    b=-g;
    dx=linprog(c,a,b,[],[]);
    x=x+dx;
    [f,g]=f_SLPclass(x);
    [gradf,gradg]=g_SLPclass(x);
    iter=iter+1;
    converged=max(abs(dx)<Tolx)&& max(g)<TolCon;
end 
fprintf('\n number of iteration	%f\n',iter);
fprintf('\n Optimum Point: (%f,%f,%f,%f,%f)\n',x1,x2,x3,x4,x5);


function [f,g]=f_SLPclass(x) %return outputs
  assert(length(x)==5, "x should be 5 elements long, but instead it is length " + length(x));
  
  xcell=num2cell(x);
  [x1,x2,x3,x4,x5]= deal(xcell{:});
  f=0.0624*(x1+x2+x3+x4+x5);
  g=-1+61/x1^3 +37/x2^3 +19/x3^3 +7/x4^3 +1/x5^3;
end
function [gradf,gradg]=g_SLPclass(x)
  assert(length(x)==5, "x should be 5 elements long, but it is only length " + length(x));
  
  xcell=num2cell(x);
  [x1,x2,x3,x4,x5]= deal(xcell{:});
gradf=0.312;
gradg=-183/x1^4 - 111/x2^4 -57/x3^4 -21/x4^4 -3/x5^4; 
end

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Catalytic]

The error message was generated by your own code, in this line

 assert(length(x)==5, "x should be 5 elements long, but instead it is length " + length(x));

Surely you put it there for a reason. Why aren't you passing a 5-element vector when your function clearly requires it?

[Ous Chkiri]

Because I have x1,x2.x3,x4 and x5