MATLAB，关于solve函数的报错

piday123

我在学习matlab符号运算这一章时尝试把书本的例子输入，发现是有误的，以下是从发现到修改的过程。
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**在这里>> a = sym('a');
6 w- V: M: R  g6 b>> b = sym('b');
>> x = sym('x');
>> y = sym('y');
>> [x,y] = solve('a*x-b*y=1','a*x+b*y=3','x','y')**

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. r- N# M. f. i4 A( \Error using solve>getEqns (line 418)
List of equations must not be empty.

Error in solve (line 226)
2 d' o; O* u7 F4 J, z) V[eqns,vars,options] = getEqns(varargin{:});
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# {  h2 z2 e0 i* U**>> [x,y] = solve('a*x-b*y=1''a*x+b*y=3','x','y')%第二次尝试修改**

Error using solve>getEqns (line 418)
5 ~: M* `( r: c& a& [  xList of equations must not be empty.
" H4 d" `9 o, ^, i! {9 W! \/ @Error in solve (line 226)
& `6 V% X6 t' o* l) |: `[eqns,vars,options] = getEqns(varargin{:});
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$ `) C5 C2 q. x* R$ Q  v+ `>> [x,y] = solve(a*x-b*y=1,a*x+b*y=3,x,y) %第三次尝试修改
[x,y] = solve(a*x-b*y=1,a*x+b*y=3,x,y)

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**
↑
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; F; v4 _* m8 B2 q4 V- @4 u/ GError: Incorrect use of ‘=’ operator. To assign a value to a variable, use ‘=’. To compare values for equality, use ‘==’.

>> [x,y] = solve(a*x-b*y== 1,a*x+b*y==3,x,y)%最终成功
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8 x1 `& t0 Q- y5 L2 Y% Cx =

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CCxiaom

这个感觉比较有用