| [ KAIST ] in KIDS 글 쓴 이(By): guest (guest) <pm475-00.dialip.> 날 짜 (Date): 2000년 12월 24일 일요일 오후 05시 35분 54초 제 목(Title): Re:Wigner distribution function % % =========================================== % Wigner distribution (prepared for MATLAB V) % =========================================== % % Change xmin,xmax,dx,pmin,pmax,dp and function psi % and make your own wigner plot ! % % Simple estimation of time : % calculation time is roughly proportional to % ((xmin-xmax)/dx)*(xmin-xmax)/dx)*(pmax-pmin)/dp) % and 600*600*200 points = 30 seconds. % xmin=-30; %=== Change here xmax=30; %=== Change here %dx=0.1; %=== Change here dx=0.2; %=== Change here pmax=2; %=== Change here pmin=-2; %=== Change here %dp=0.02; %=== Change here dp=0.1; %=== Change here x=xmin:dx:xmax; y=xmin:dx:xmax; p=pmin:dp:pmax; [X,Y]=meshgrid(x,y); % % If your function is psi(x) % psi2(x,y)=complex conjugate psi(x+y) % % So, for example, if % psi(x)=exp(-(x-posi)^2/width)+exp(-(x+posi)^2/width) % (double gaussian or double slit) % posi=7;width=3; % then % psi1=exp(-(X-Y-posi).^2/width)+exp(-(X-Y+posi).^2/width); % psi2=exp(-(X+Y-posi).^2/width)+exp(-(X+Y+posi).^2/width); % % ======= change your function from here posi=7; width=2; psi1=exp(-(X-Y-posi).^2/width^2)+exp(-(X-Y+posi).^2/width^2); psi2=exp(-(X+Y-posi).^2/width^2)+exp(-(X+Y+posi).^2/width^2); % ====== to here [P,PY]=meshgrid(p,y); PPY=P.*PY; wig=(psi1'.*conj(psi2)')*exp((2*i*PPY)); subplot(2,1,1); mesh(x,p,real(wig')); subplot(2,1,2); mesh(x,p,imag(wig')); xlabel('x'); ylabel('p'); % ======= another good viewangle %view(0,90) % %jwahn@umich.edu 10/20/98 % |