Substitute multiple values to array of expressions

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I have the following code that forms 4 symbolic equations (xs1, xs2, xs3, xs4) using 4 symbolic variables (x1, x2, x3, x4). Problem is, I cannot substitute numeric values into the equations.
A=[9,1,1,1;1,8,1,1;1,1,7,1;1,1,1,6];
B=[75;54;43;34];
x=sym('x',[1 4]);
xs=sym('xs',[1 4]);
xs(1:4)=0;
for i=1:4
for j=1:4
if(j==i)
continue
end
xs(i)=xs(i)-x(j);
end
xs(i)=1/A(i,i)*(B(i)+xs(i));
end
What I tried,
x(1:4)=0;
subs(xs);
%another one
subs(xs(1),{x(1),x(2),x(3),x(4)},{[0,0,0,0]})
None worked. How do I do this?

Risposta accettata

Star Strider
Star Strider il 19 Mag 2019
The ‘x’ values are not ‘x1’, ‘x2’, ..., but ‘x(1)’, ‘x(2)’, ...
Try this instead:
q = subs(xs(1),{x(1),x(2),x(3),x(4)},{[0,0,0,0]});
(Asssign it to whatever variable name you want.)
  2 Commenti
Yavuz Selim Tozlu
Yavuz Selim Tozlu il 19 Mag 2019
I'm pretty sure I've tried this before, and it didn't seem to work back then. Now it works just fine. I was probably doing something wrong. Thanks!

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