Matlab 变量值直接输出 和 sprintf输出 不同是怎么回事？

ubeautqq

nitao=2.175;
: s- \: e" S+ Z6 k' k) W5 Hnitae=2.18;
4 C0 T+ S. F# V/ Sderta33=30.3;
derta13=5.7;
L=0.1;%m
; K7 s% O8 ?$ K2 o) ^lamda0=0.633*10^(-6);%m
Vm=100;%v
1 q" J  n& c% }8 Be=43;
5 I# _; m9 F; H" L; D* Y4 {A=10^(-3);%m^2
dertaf=10^7;%Hz

syms Ez;
E=solve(2*pi*L/lamda0*((nitao-nitae)+Ez*(nitae^3*derta33-nitao^3*derta13)/2)==pi,Ez);
! R/ `8 u5 E5 Z# \; KE
sprintf('半波电场强度：%e','E')

Vpi=E*L;
dertaph=Vm*pi/Vpi;
dertaph
. ~8 V& e: V. V* q6 b, gsprintf('相位延迟：%e','dertaph')

; c2 f. |3 g4 x$ h( RP=e*A*Vpi^2*dertaph^2*dertaf/(pi*L);
P
sprintf('驱动功率%e','P')
$ `! _$ Y- L. O: R
& E0 A3 X6 n* B. h- p9 U! u( q
$ B( d& Q7 Z) M: @6 P结果：
E =
(9444732965739290427392*pi)/1196549586897533007794808436155 + 11258999068427/287405211048345088
: ^$ j. |$ Q# w' T+ k, U! @ans =
' M$ Q" P, o- M8 i半波电场强度：6.900000e+01
dertaph =
) g! J$ I' O* H" p% F+ t  V0 U(100*pi)/((4722366482869645213696*pi)/5982747934487665038974042180775 + 11258999068427/2874052110483450880)
' i: t9 e4 C. F% }% i/ Z9 Gans =
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
( Q; A+ n$ d; ~% r& C$ J$ X. [P =
  N" {& d- r; B/ U. j( u0 ~. J8 f43000000000*pi
ans =
驱动功率8.000000e+01
为什么变量值和sprintf的值不一样？
为什么相位延迟有这么多个？
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kinidrily

之前遇到过
, G( ~+ F- S1 g/ Y- B) d

• 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))
  4 h& N: t, Q. ?  ], D+ W; ^

; N5 _2 }& \8 t1 t) K
2 W5 g4 ?( @' {, I7 G  p就得到：
+ S9 o/ D6 }/ q; A
E =
(9444732965739290427392*pi)/1196549586897533007794808436155 + 11258999068427/287405211048345088
) W5 P$ z- l  ~! U2 ]9 U; W* ~0 o ans =
半波电场强度：3.919945e-05
0 X: @. G# u" w4 \$ |dertaph =
(100*pi)/((4722366482869645213696*pi)/5982747934487665038974042180775 + 11258999068427/2874052110483450880)
) V! ?, J3 U% p8 b5 u4 q ans =
相位延迟：8.014380e+07
P =
43000000000*pi
: `; g: [( \" J; f! c! f ans =
驱动功率1.350885e+11


. d9 L/ g4 o0 E0 ?是符合的
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yxlk

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