求助,出错了?
figure('pos',,'color','w');axes('pos',);
syms s t
T=2;K=1;
T1=sym(num2str(T));K1=sym(num2str(K));
m0=2;e0=2;gs=m0/e0;rt=2;et1=rt;
for tt=0:0.05:20;
if et1>e0,eout=m0;
elseif et1<-e0,eout=-m0;
else eout=gs*et;
end
ee=sym(num2str(eout));
y1=ilaplace(K1*ee/s/(T1*s^2+s+1));
et=rt-y1;det=diff(et);
et1=subs(et,tt);det1=subs(det,tt);
plot(et1,det1);hold on;
end
grid
??? Function 'max' is not defined for values of class 'sym'.
Error in ==> num2str at 70
xmax = double(max(abs(x(:))));
是什么错误呢? 原帖由 jennychung 于 2007-4-1 20:29 发表
figure('pos',,'color','w');
axes('pos',);
syms s t
T=2;K=1;
T1=sym(num2str(T));K1=sym(num2str(K));
m0=2;e0=2;gs=m0/e0;rt=2;et1=rt;
for tt=0:0.05:20;
if et1>e0,eout=m0;
elseif e ...
max 函数不支持符号变量,建议先阅读matlab基础书,而不是一遇到问题就发问
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