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');
8 x& e# |; O9 a" V- u>> b = sym('b');
>> x = sym('x');
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>> [x,y] = solve('a*x-b*y=1','a*x+b*y=3','x','y')**
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Error using solve>getEqns (line 418)
List of equations must not be empty.
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Error in solve (line 226)
$ E2 P3 b1 v3 ^# ^+ v[eqns,vars,options] = getEqns(varargin{:});
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4 J/ E% Y: ]' b/ I**>> [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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( S2 }! s; t" {" Z% l  F$ m/ |) fError using solve>getEqns (line 418)
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Error in solve (line 226)
[eqns,vars,options] = getEqns(varargin{:});
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**
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% y$ y( k" s; e>> [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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Error: Incorrect use of ‘=’ operator. To assign a value to a variable, use ‘=’. To compare values for equality, use ‘==’.
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% [4 i* q% i7 t  r>> [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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CCxiaom

这个感觉比较有用