help --- symbolic expression or function

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justlikethat
justlikethat am 11 Jun. 2021
Kommentiert: justlikethat am 11 Jun. 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!

Akzeptierte Antwort

Walter Roberson
Walter Roberson am 11 Jun. 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 Kommentar
justlikethat
justlikethat am 11 Jun. 2021
Thank you so much!
Looks like the data I saw was out of date.

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Weitere Antworten (1)

KSSV
KSSV am 11 Jun. 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 Kommentar
justlikethat
justlikethat am 11 Jun. 2021
Thank you so much!
Looks like the data I saw was out of date.

Melden Sie sich an, um zu kommentieren.

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