help --- symbolic expression or function

3 vues (au cours des 30 derniers jours)
justlikethat
justlikethat le 11 Juin 2021
Commenté : justlikethat le 11 Juin 2021
I've created a code for the symbol variables.
But I'm very embarrassed because the same error keeps coming out.
I'd appreciate it if you could tell me the solution.
syms x y z
one = sym('3*x +2*y - z = 10');
two = sym('-x + 3*y + 2*z = 5');
three = sym('x -y - z = -1');
[x,y,z] = solve(one,two,three)
error messeage ---->
The text vector and string type of the first argument can only specify variables or numbers. Use 'str2sym' to evaluate the string type and the text vector representing the symbol expression.
Error occurred: sym>tomupad (Line 1296)
S = convertChar(x);
Error occurred: sym (Line 234)
S.s = tomupad(x);
Error occurred: symsolve (Line 2)
one = sym('3*x +2*y - z == 10');
My grammar may be wrong because I am not good at English. Thank you!

Réponse acceptée

Walter Roberson
Walter Roberson le 11 Juin 2021
The code you are using has not been valid since about R2017b.
syms x y z
one = str2sym('3*x +2*y - z = 10');
two = str2sym('-x + 3*y + 2*z = 5');
three = str2sym('x -y - z = -1');
[x,y,z] = solve(one,two,three)
x = 
y = 
5
z = 
but better would be
syms x y z
one = 3*x +2*y - z == 10;
two = -x + 3*y + 2*z == 5;
three = x -y - z == -1;
[x,y,z] = solve(one,two,three)
x = 
y = 
5
z = 
  1 commentaire
justlikethat
justlikethat le 11 Juin 2021
Thank you so much!
Looks like the data I saw was out of date.

Connectez-vous pour commenter.

Plus de réponses (1)

KSSV
KSSV le 11 Juin 2021
syms x y z
one = 3*x +2*y - z == 10;
two = -x + 3*y + 2*z == 5;
three = x -y - z == -1 ;
s = solve({one,two,three},x,y,z) ;
[s.x s.y s.z]
  1 commentaire
justlikethat
justlikethat le 11 Juin 2021
Thank you so much!
Looks like the data I saw was out of date.

Connectez-vous pour commenter.

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