MATLAB's drawnow doesn't flush -


is there reason matlab's drawnow wouldn't flush?

this code:

j=1; k = 1:length(p)     = 1:n         plot(p(k,j),p(k,j+1),'.');         j = j+2;     end     axis equal     axis([-l l -l l]);     j=1;     drawnow end

(rungekutta4 own function wrote, , works ok, problem isn't there.)

the particles stay drawn on plot , don't overwritten every time loop executes.

how fix problem?

the proper , efficient way handle graphics. should vectorize plot commands.

% example data make runnable l = 1; n = 10; % number of points p = 2*rand(1e2,n+1)-1;  % initialize plot, first iteration h = plot(p(1,1:n),p(1,2:n+1),'.'); % plot first set of points , return handle axis equal; axis([-l l -l l]); hold on; % ensure axis properties fixed drawnow;  % animate k = 2:size(p,1) % size safer in case     % use handle update positions of plotted points     set(h,{'xdata','ydata'},{p(k,1:n),p(k,2:n+1)});     drawnow;     pause(0.1); % slow down animation bit make visible end

calling clf and/or plot on each iteration of animation causes many things in memory unnecessarily deleted , reallocated, resulting slower code. may result in flickering in cases.

see this similar question , answer.


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