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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$ ], i& C/ f7 k' r& B$ J**在这里>> a = sym('a');
0 k8 V0 l! ~) V8 y4 ]>> b = sym('b');
>> x = sym('x');
>> y = sym('y');
! n! g+ e' |9 _& w>> [x,y] = solve('a*x-b*y=1','a*x+b*y=3','x','y')**

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4 X- e, ?) Y* I( @Error using solve>getEqns (line 418)
List of equations must not be empty.

6 s! T4 I2 v6 Q' D  L( S- x+ BError in solve (line 226)
! {1 x* N0 d1 ?4 L, Y' c1 Z[eqns,vars,options] = getEqns(varargin{:});
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**>> [x,y] = solve('a*x-b*y=1''a*x+b*y=3','x','y')%第二次尝试修改**
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7 i1 z, D% S8 b0 eError using solve>getEqns (line 418)
List of equations must not be empty.
Error in solve (line 226)
[eqns,vars,options] = getEqns(varargin{:});

**
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>> [x,y] = solve(a*x-b*y=1,a*x+b*y=3,x,y) %第三次尝试修改
2 Y* y# M+ L7 `6 Q [x,y] = solve(a*x-b*y=1,a*x+b*y=3,x,y)
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**
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  t* J$ E5 D& w' ?/ lError: 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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x =
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y =
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1/b
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CCxiaom

这个感觉比较有用