無(wú)阻尼二自由系統(tǒng)固有頻率的程序

shouce

% 無(wú)阻尼二自由系統(tǒng)固有頻率的程序 20180401A
: ?, i8 Q, |- V7 ~m1=100;m2=100;k1=200;k2=400;%
% E$ R7 |5 C, rc1=0;c2=0;
2 t( k" H6 d& ^! C5 H) `. zx0=[1;0];xd0=[0;0];tf=50;dt=0.1;
6 x  e- K$ ?/ t* XM=[m1,0;0,m2];k=[k1+k2,-k2;-k2,k2];
c=[c1+c2,-c2;-c2,c2];
A=[zeros(2,2),eye(2);-M\k,-M\c];
0 C5 T8 S/ s, p" hy0=[x0;xd0];
9 _  j0 o) Y- l4 a4 h& pfor i=1:round(tf/dt)+1
    t(i)=dt*(i-1)
    y(:,i)=expm(A*t(i))*y0;
6 F0 A, K) V8 t" s3 C$ [end
subplot(2,1,1),plot(t,y(1,),grid  
subplot(2,1,2),plot(t,y(2,),grid
; v4 \. B$ B5 v0 O* i[p,lamda]=eig(A)

  o3 |7 w' X7 i) l! f
! T/ K9 R7 H3 M+ C) e( Q
5 M9 s$ a& D( _$ [
lamda =
  Columns 1 through 2
0 T& ~2 w, [7 u  0.000000000000000 + 3.020447918044219i  0.000000000000000 + 0.000000000000000i
( i: x+ Q. h5 t0 a; j( g) o3 A* f8 A3 S  0.000000000000000 + 0.000000000000000i  0.000000000000000 - 3.020447918044219i
7 {" W/ f2 F2 r6 ^4 X4 ~7 k2 I  0.000000000000000 + 0.000000000000000i  0.000000000000000 + 0.000000000000000i
  0.000000000000000 + 0.000000000000000i  0.000000000000000 + 0.000000000000000i
2 C' @2 z5 V6 N' `  Columns 3 through 4
  0.000000000000000 + 0.000000000000000i  0.000000000000000 + 0.000000000000000i
  0.000000000000000 + 0.000000000000000i  0.000000000000000 + 0.000000000000000i
% M( F, P/ u; ^9 j8 n" D# T- e7 @ -0.000000000000000 + 0.936426384924271i  0.000000000000000 + 0.000000000000000i
  0.000000000000000 + 0.000000000000000i -0.000000000000000 - 0.936426384924271i
$ k& d3 q" U- E2 V


, |9 y5 {; e2 ?/ C' ^6 }

鴻鵠重工

代碼中有個(gè)笑臉是啥意思，此處應(yīng)該是什么代碼,？