Change of intensity of old points in animation

Hi,

I have three variable X, Y, Z of length 10000 points each .Z represent signal strength. I need to generate animated X,Y plot (scatter) with signal strength represented by color. For persistanace i am plotting 10 new color coded points each frame and making old points white . Code given below.

for i1 = 1:10:(numpoints-10),
    plot(xP(1:i1-1),yP(1:i1-1),'w.','markersize',18) ;% Making old points to white
    hold on
    scatter(xP(i1+(0:9)),yP(i1+(0:9)),32,zP(i1+(0:9)),'filled') % Adding 10 new points for persistence
    set(gca,'Color','k');
    axis([xMin, xMax, yMin, yMax])
    caxis([zMin, zMax])
    hold off;
    drawnow
end

Instead of making all the old points 'White' , I want to start with grey scale and increase an old point's intensity (alpha) every time, when any of newly added 10 point is same as old point. I would appreciate any suggesion in towards solution.

regards

jayant

Answer 1

[Jayant chouragade]

% 

Solved this with below code.

signal_peaks= Normalised Signal Amplitude for given (xP,yP).

signal_peaks1=zeros(1,length(signal_peaks));
for i1 = 10:10:(numpoints-10),
     UB=(i1);
     LB=(i1-9);
     AB=[xP(1:LB)' yP(1:LB)'];
     AB_new=[xP(LB:UB)' yP(LB:UB)'];
     LIA=ismembertol(AB,AB_new,0.01,'ByRows',true);
     signal_peaks1(1:LB)=signal_peaks1(1:LB)+ double(LIA)'.*signal_peaks(1:LB); %% Keep adding the intensity every time point is repeated on that location. 
     colors=gray(10000);
     colormap(colors);
     set(gca,'Color','k');
     colormap jet;    
    scat2= scatter(xP(1:i1-1),yP(1:i1-1),'w.','markersize',18) ;% Making old points to white
    scat1.MarkerFaceAlpha=0.3;
    hold on
    scatter(xP(LB:UB),yP(LB:UB),3,signal_peaks1(LB:UB),'filled','o') % Adding 10 new points for persistence
    hold off;
    drawnow
end