Matlab 变量值直接输出 和 sprintf输出 不同是怎么回事？

ubeautqq

nitao=2.175;
nitae=2.18;
' Q# R9 W+ X9 v4 n: tderta33=30.3;
derta13=5.7;
9 B8 @- o) J' j/ }6 O3 cL=0.1;%m
# k- _. H2 q$ b& O- O$ G! E" [2 ilamda0=0.633*10^(-6);%m
9 \2 w$ V3 w' ?) X! z2 SVm=100;%v
, j* f6 _$ [9 g+ y/ \" t0 o0 }: Ge=43;
! q+ O5 R/ X0 TA=10^(-3);%m^2
( m9 {2 I; ]: p4 Ydertaf=10^7;%Hz

syms Ez;
& l0 H( n) r& ~- m# JE=solve(2*pi*L/lamda0*((nitao-nitae)+Ez*(nitae^3*derta33-nitao^3*derta13)/2)==pi,Ez);
E
! S8 Q( Y" G3 Csprintf('半波电场强度：%e','E')

4 C9 D, h+ g  R9 ZVpi=E*L;
( p. j& @" z/ E' U/ D, H4 V7 R' Cdertaph=Vm*pi/Vpi;
dertaph
sprintf('相位延迟：%e','dertaph')

/ X6 ?0 q* L: G/ D& lP=e*A*Vpi^2*dertaph^2*dertaf/(pi*L);
' f, h/ p9 _( p- aP
sprintf('驱动功率%e','P')
  T4 z- r2 @7 I- [/ M' D) S

  _. Z# M* V5 y. _结果：
) |$ \" t, N2 D. oE =
(9444732965739290427392*pi)/1196549586897533007794808436155 + 11258999068427/287405211048345088
ans =
4 i4 i# {# w1 @半波电场强度：6.900000e+01
dertaph =
(100*pi)/((4722366482869645213696*pi)/5982747934487665038974042180775 + 11258999068427/2874052110483450880)
ans =
- ~8 v3 G$ z5 |6 v) k/ l, P  c相位延迟：1.000000e+02相位延迟：1.010000e+02相位延迟：1.140000e+02相位延迟：1.160000e+02相位延迟：9.700000e+01相位延迟：1.120000e+02相位延迟：1.040000e+02
P =
) a# }# \( k: a9 l6 h43000000000*pi
" E/ }9 t6 b; v) P- D. N7 S, ians =
驱动功率8.000000e+01
为什么变量值和sprintf的值不一样？
# ]3 D: u8 G3 X7 `  e为什么相位延迟有这么多个？
) h: ~6 O3 p7 x: U' f

kinidrily

之前遇到过
2 X' \% y% n9 p) F. R

• syms Ez;
• E=solve(2*pi*L/lamda0*((nitao-nitae)+Ez*(nitae^3*derta33-nitao^3*derta13)/2)==pi,Ez);
• E
• sprintf('半波电场强度：%e',double(E))
• 
  
• Vpi=E*L;
• dertaph=Vm*pi/Vpi;
• dertaph
• sprintf('相位延迟：%e',double(dertaph))
• 
  
• P=e*A*Vpi^2*dertaph^2*dertaf/(pi*L);
• P
• sprintf('驱动功率%e',double(P))
    s: ^2 t8 W1 u/ o/ j6 a9 T3 m

) t3 n; L1 n9 }0 y- ~
- A6 I, |: q- ~# n4 I就得到：
( `/ D4 Z+ J0 x2 a8 h
E =
(9444732965739290427392*pi)/1196549586897533007794808436155 + 11258999068427/287405211048345088
ans =
半波电场强度：3.919945e-05
dertaph =
7 w1 }& p+ }2 ]& u(100*pi)/((4722366482869645213696*pi)/5982747934487665038974042180775 + 11258999068427/2874052110483450880)
ans =
7 k; V/ S5 r- X* ^; c+ o0 F相位延迟：8.014380e+07
P =
: T. c8 L, @; W3 r# k% {3 P 43000000000*pi
1 [+ \3 n, h4 m8 t3 V: E$ e ans =
6 n2 z$ s; z+ u. O/ C' W3 C驱动功率1.350885e+11

4 D$ z* l6 h0 Z5 b' `4 ~* ]8 q, O$ l
( p% k8 j5 }% ]9 s是符合的

yxlk

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