TA的每日心情 | 开心 2019-11-29 15:38 |
|---|
签到天数: 4 天 [LV.2]偶尔看看I
|
EDA365欢迎您登录!
您需要 登录 才可以下载或查看,没有帐号?注册
x
t2 U0 L* p" E p
2 v! |. _& ]0 y3 z% b& a
这是书上的一段代码,但是用18的matlab运行不了,想请教一下大神如何修改才能运行呢?感谢!
# S3 N: \. k% d0 C( v5 |0 qsyms a b x;' E( k3 b8 E; K. X4 Z8 l# i ^
f1=a*sin(x)+b" \2 d$ [; B4 h) F! @2 b
f2=subs(f1,sin(x),'log(y)')( T% x" @7 v4 z6 L% Q8 A
class(f2)+ g' L" Q, t h+ L- G# ~% l4 x' k
f3=subs(f1,a,sym(3.11))
# u8 J* a/ O: D: U- t2 H( T! Q5 L+ rclass(f3)+ M0 f& I3 V7 L, ?
f4=subs(f1,x,[0,pi/2,pi]); l/ W4 u/ v" C* W
class(f4)& x: e I% {# l" ~$ o( s
format
0 u8 m8 C' @7 iformat compact
" j7 ~. h# c7 b- y Qt=0:pi/10:2*pi;
8 S5 A* k; z4 K' A' A6 Bf5=subs(f1,{a,b,x},{2.3,t});
6 Z6 G, b* x% v) F, gclass(f5)! m- P e9 @$ G! j6 E, p" i
plot(t,f5,'r:','LineWidth',5)! r: D- n/ h9 W
k=[0.6;0.8;1];) u& z+ S) k0 o. Q1 ~& @
f6=subs(subs(f1,{a,b},{k,2}),x,t);6 J, d: \- L6 K* K. v- x6 N+ t; Y
class(f6)
8 k$ [+ [/ o, o% Rplot(t,f6)
' Z2 t$ j7 R( X2 c4 {. ~' |3 L& g0 K0 A0 T3 L- B" h
1 {) o$ l# U p8 J6 K) m0 e
提示错误信息
- U* u' W' J9 B9 B: w% {. Y错误使用 sym>convertChar (line 1448)6 x" p% ?: j/ Z, Z
Character vectors and strings in the first argument can only specify a variable or number. To evaluate character vectors and strings \& e g- n ]! c, J
representing symbolic expressions, use 'str2sym'.
1 W! H. L- H/ b1 L5 x7 e2 m
" z# e5 b) _4 S. r" E0 r }
8 o' U4 d; C+ z5 e$ W: b6 z出错 sym>tomupad (line 1214)
. |* t! l$ ^- m3 I8 B& U1 a S = convertChar(x);1 n" |) i# h5 ?( r$ u3 [' ?$ Z
# \6 D- L, v: v3 d: A7 u! @: k' J. O0 y; `- e% [; U% P+ I
出错 sym (line 211)
" {9 l0 l' k$ |/ _/ h9 R+ D" ?0 j S.s = tomupad(x);1 t! V6 \" b3 A, |9 Z
3 P$ O( x0 F% j/ I7 t( J' w
5 N1 J+ F1 f6 J3 q. H! o7 |
出错 sym/subs>normalize (line 211)( D& ~; ~9 g T- A" D4 e7 g b
Y = {sym(Y)};
6 Z% V ?. g; X0 D7 S+ s6 i) K3 h6 N- q7 s
" ~0 z: e9 z- G7 E; g# g出错 sym/subs>mupadsubs (line 157)
/ a( W" J' _- P& U[X2,Y2,symX,symY] = normalize(X,Y); %#ok7 Y3 r# H) l; r1 Q* c
8 V4 n6 w8 U1 Q1 y
& G% C" k3 X) r* R: Y' r3 ^7 s7 {出错 sym/subs (line 145)# i) b8 \2 @# T
% A- \7 e/ H8 T9 [
G = mupadsubs(F,X,Y); |
|