📄 bifurcation.m
字号:
function bifurcation(action)
%
%Bifurcation - grafical interface for bifurcation ploting
%
% Click "Start" button in order to begin the simulation.
% You can stop the simulation at any time by pressing the "Stop"
% button.
% Using the "New plot" button a new figure is displayed with the obtained
% bifurcation.
% "Help" button displays this message.
% Use "Exit" button in order to close the graphical interface and clear
% all used variables.
%
% A time discrete chaotic generator can be selected in the upper part of the graphical
% interface. Use the "..." (browse) button in order to select a
% specific chaotic generator from the list.
%
% From the graphical interface the following parameters can be modified:
% - Param. range: range of the parameter of the chaotic generator ;
% - Nb. of points: number of points used for each parameter value in
% order to construct the bifurcation diagram;
% - Plotting style: "0" use dots and "1" use a continuous line for plotting
% the attractor;
% - Time range: discrete time range for the state variable of the chaotic
% generator;
% - Select variable: state variable used to plot the bifurcation diagram;
% - Initial cond: initial conditions for the chaotic generator;
%
% In the bottom of the figure is displayed current value of the parameter
%
% The available time discrete chaotic generators are:
% - BernoulliMap: Bernoulli map
% x[n] = mod(k*x[n-1], 1)
% where k arbitrary
% - genhaos: chaos generator with a recursive structure
% x[n] = f(k[1]*x[n-1]+k[2]*x[n-2]+k[3]*x[n-3])
% where f(x) = x-2*floor((x+1)/2), k[1] arbitrary, k[2] = k[3] = 1
% - henonmap: Henon map
% x[n] = 1-alpha*x[n-1]^2+y[n-1];
% y[n] = beta*x[n-1];
% where alpha arbitrary, beta = 0.3
% - logisticmap1: logistic like map 1
% x[n] = (k^2)*x[n-1]*(1-x[n-1])*((1-2*x[n-1])^2);
% where k arbitrary
% - logisticmap2: logistic like map 2
% x[n] = k*x[n-1]*(0.75-(x[n-1]^2))
% where k arbitrary
% - logisticmap3: logistic like map 3
% x[n] = k*x[n-1]*(1.25-(5*(x[n-1]^2))+(4*(x[n-1]^4)))
% where k arbitrary
% - logisticmap: logistic map
% x[n] = k*x[n-1]*(1-x[n-1])
% where k arbitrary
% - miramap: Mira map
% x[n] = y[n-1]
% /
% | -a*x[n-1] , if x[n-1]<6
% y[n] = y[n-1]+ |
% | lambda*x[n-1]-6*(a+lambda), otherwise
% \
% where a arbitrary, lambda = 2
% - PWAMmap1: piece wise affine Markov map 1
% /
% | B*(D-abs(x[n-1])) , if abs(x[n-1])<=D
% x[n] = |
% | B*(abs(x[n-1])-2*D) , otherwise
% \
% where B arbitrary, D = 1
% - PWAMmap2: piece wise affine Markov map 2
% /
% | -B*abs(x[n-1]) , if abs(x[n-1])<=D
% x[n] = |
% | -B*(abs(x[n-1])-2*D) , otherwise
% \
% where B arbitrary, D = 1
% - PWAMmap3: piece wise affine Markov map 3
% /
% x[n] = | -B*x[n-1] , if abs(x[n-1])<=D
% | B*(x[n-1]-2*D*sign(x[n-1])) , otherwise
% \
% where B arbitrary, D = 1
% - PWAMmap4: piece wise affine Markov map 4
% /
% | B*(-x[n-1]+D*sign(x[n-1])) , if abs(x[n-1])<=D
% x[n] = |
% | B*(x[n-1]-2*D*sign(x[n-1])) , otherwise
% \
% where B arbitrary, D = 1
% - TailedTentMap: tailed tent map
% x[n] = 1-2*abs(x[n-1]-((1-k)/2))+max(x[n-1]-1+k,0)
% where k arbitrary
% - tentmap1: tent like map 1
% /
% | k*x[n-1] , if (0<=x[n-1]) & (x[n-1]<1/3)
% x[n] = | k*(2/3-x[n-1]) , if (1/3<=x[n-1]) & (x[n-1]<2/3)
% | k*(-2/3+x[n-1]), otherwise
% \
% where k arbitrary
% - tentmap2: tent like map 2
% /
% | k*x[n-1] , if (0<=x[n-1]) & (x[n-1]<1/4)
% x[n] = | sqrt(k)*(1-2*x[n-1]) , if (1/4<=x[n-1]) & (x[n-1]<1/2)
% | sqrt(k)*(2*x[n-1]-1) , if (1/2<=x[n-1]) & (x[n-1]<3/4)
% | k*(1-x[n-1]) , otherwise
% \
% where k arbitrary
% - tentmap: tent map
% x[n] = k*(1-abs(1-2*x[n-1]))
% where k arbitrary
if nargin==0
%set paths
addpath([pwd '\Discr']);
addpath([pwd '\Prvt']);
%initialize GUI
srtBifurcationGUI;
%set default generator (logisticmap)
% d=dir('Discr');
% str = {d.name};
% s=cell2struct(str(3),{'str'},1);
% fcname=s.str(1:end-2);
fcname = 'logisticmap';
hndf=gcf;
set(findobj(hndf,'Tag','edtTitle'),'FontSize',10,'String',fcname)
%set default values
structData=BifInit(fcname);
vParamRg=structData.ParamRg;
nNbPts=structData.NbPts;
vTimeRange=structData.TimeRange;
nSelVar=structData.SelVar;
y0=structData.InitCond;
if ~isempty(vParamRg) | ~isempty(nNbPts) | ~isempty(vTimeRange) | ~isempty(nSelVar) | ~isempty(y0)
%display default values
plot(0.5,0.5)
cla
set(findobj(hndf,'Tag','edtParamRg'),'String',num2str(vParamRg,4));
set(findobj(hndf,'Tag','edtNbPts'),'String',num2str(nNbPts));
set(findobj(hndf,'Tag','edtTimeRange'),'String',num2str(vTimeRange,4));
set(findobj(hndf,'Tag','edtSelVar'),'String',num2str(nSelVar,2));
set(findobj(hndf,'Tag','edtInitCond'),'String',num2str(y0,3));
set(findobj(hndf,'Tag','txtVal'),'String',[])
end
elseif strcmp(action,'Start')
hndf=gcf;
%set buttons
set(findobj(hndf,'Tag','btnStop'), 'Enable', 'on');
set(findobj(hndf,'Tag','btnNewPlot'), 'Enable', 'off');
set(findobj(hndf,'Tag','btnExit'), 'Enable', 'off');
set(findobj(hndf,'Tag','btnBrowse'), 'Enable', 'off');
%get current values
fcname=get(findobj(hndf,'Tag','edtTitle'),'String');
vParamRg=str2num(get(findobj(hndf,'Tag','edtParamRg'),'String'));
nNbPts=str2num(get(findobj(hndf,'Tag','edtNbPts'),'String'));
vTimeRange=str2num(get(findobj(hndf,'Tag','edtTimeRange'),'String'));
nSelVar=str2num(get(findobj(hndf,'Tag','edtSelVar'),'String'));
y0=str2num(get(findobj(hndf,'Tag','edtInitCond'),'String'));
%bifurcation
ud.xpts=[];
ud.ypts=[];
ud.stop=0;
for k_var=vParamRg(1):(vParamRg(2)-vParamRg(1)+1)/nNbPts:vParamRg(2)
%solver
[T,Y]=m_dreTF(fcname,vTimeRange,y0,k_var);
xutil=Y(1,nSelVar);
%eliminate redundant points
for n=2:length(Y(:,nSelVar))
if xutil~=Y(n,nSelVar)
xutil=[xutil;Y(n,nSelVar)];
end
end
ud.xpts=[ud.xpts; k_var*ones(length(xutil),1)];
ud.ypts=[ud.ypts; xutil];
set(gcf,'UserData',ud)
if k_var==vParamRg(1)
hpts=plot(ud.xpts,ud.ypts,'.','MarkerSize',1,'EraseMode','none');
set(gca,'XLimMode','manual','YLimMode','manual')
xmin=min(ud.xpts);
xmax=max(ud.xpts)+0.1;
ymin=min(ud.ypts)-0.1;
ymax=max(ud.ypts)+0.1;
axis([xmin xmax ymin ymax])
else
xlim = get(gca,'xlim');
ylim = get(gca,'ylim');
%replot everything if out of axis range
if (k_var < xlim(1)) | (xlim(2) < k_var) | (min(xutil) < ylim(1)) | (ylim(2) < max(xutil))
xmin=xlim(1);
xmax=xlim(2);
ymin=ylim(1);
ymax=ylim(2);
if k_var < xlim(1)
xmin=k_var-0.1;
elseif xlim(2) < k_var
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -