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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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u7 {- I2 c! |5 e; K' w& O**在这里>> a = sym('a');
8 U7 o( l1 D- X>> b = sym('b');
6 X; L) ~. _. p% C! z>> x = sym('x');
3 A1 b. h3 M$ v: J! _>> y = sym('y');
! R3 E, T' a1 w( _+ y, J>> [x,y] = solve('a*x-b*y=1','a*x+b*y=3','x','y')**% C5 S4 S# F- f+ e |, f
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; t4 z: H, n. g& I- ]5 m d5 e7 x& vError using solve>getEqns (line 418)# K& b G, k- P+ }
List of equations must not be empty.
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/ Q% R' K" a; P& xError in solve (line 226)
" V/ P) c' W! u+ j3 J0 M5 }! ][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**' s4 a' e1 C( H6 |8 _5 Q
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Error using solve>getEqns (line 418)
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Error in solve (line 226)
$ S4 a" S$ K r7 h% E. z[eqns,vars,options] = getEqns(varargin{:});
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**
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2 r: f/ _6 w& X2 B>> [x,y] = solve(a*x-b*y=1,a*x+b*y=3,x,y) %第三次尝试修改; W) v h/ ?/ q; o5 ` W
[x,y] = solve(a*x-b*y=1,a*x+b*y=3,x,y)' o- j C: T! Y" d( M+ k
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**
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$ F: h0 z' s+ e( jError: Incorrect use of ‘=’ operator. To assign a value to a variable, use ‘=’. To compare values for equality, use ‘==’.& z: y: v7 r5 j* T) W6 e3 m
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>> [x,y] = solve(a*x-b*y== 1,a*x+b*y==3,x,y)%最终成功
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x =2 E2 V5 F1 }3 h1 ^5 ^! i; \3 B
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+ n/ l. _! F/ ^. }6 V9 \7 B! Ty =
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1/b
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发表于 2020-6-17 18:45
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淘帖
支持！
反对！