syms 出错(MATLAB(R2008b))

.m文件为
syms x
y=x.^2;
diff(f)

command 窗口
??? Error using ==> mupadinit at 35
Unable to initialize kernel

Error in ==> mupadengine.mupadengine>mupadengine.evalin at 115
[result,status] = mupadmex(statement,8);

Error in ==> C:\Program Files\MATLAB\R2008b\toolbox\symbolic\symengine.p>symengine at 25

Error in ==> sym.sym at 69
eng = symengine;

Error in ==> syms at 77
assignin('caller',x,sym(x));

Error in ==> Untitled at 1
syms x
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它老提示mupadinit at 35出错,请问是不是这个文件坏了?

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如果仅是正链旁题中所述3行代码唤斗的话，是可以运行的，不过第三行应该是对函数y求举橡微分，f改为y要是还不能运行，应该是文件出问题了

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