[EDIT2] I am using the code below to plot a real time signal from serial port.
The issue I have is that the plot lags a lot even though I am not replotting the whole screen.
How can I speed up the process?
function timerCallback(~,~,hObject)
handles = guidata(hObject);
[r,w]=size(handles.y);
if isfield(handles,'s')
try
readasync(handles.s);
n = handles.s.BytesAvailable;
if n > 0
in = fscanf(handles.s,'%d');
handles.y=[handles.y,in];
guidata(hObject,handles);
set(handles.h,'yData',(handles.y-99)*26/855);
startSpot = (w)-1000;
axis([ startSpot, (w+50), 0 , 30 ]);
drawnow
end
catch
end
end
Timer is set to fixedRate at 0.001s.
[EDIT2]
I have moved the plot line outside the timer callback. I can't barely see any difference in performance.
Related
I've written a tkinter script with animation, that works fine on Xubuntu, but when I run it on Mac, the animation doesn't work. Here's a little script that demonstrates the problem:
import tkinter as tk
from time import sleep
root = tk.Tk()
canvas = tk.Canvas(root, height=200, width = 200)
canvas.pack()
this = canvas.create_rectangle(25,25, 75, 75, fill='blue')
that = canvas.create_rectangle(125, 125, 175, 175, fill = 'red')
def blink(event):
global this, that
for _ in range(9):
canvas.itemconfigure(this, fill='red')
canvas.itemconfigure(that, fill = 'blue')
canvas.update_idletasks()
sleep(.4)
this, that = that, this
canvas.bind('<ButtonRelease-1>', blink)
root.mainloop()
This draws a red square and a blue square on a canvas. When the user clicks the canvas, the squares repeatedly switch colors. On Xubuntu, it works as intended.
On Mac, when I click the canvas, I get spinning beach ball, and after a few seconds, we see that squares have switched colors, because they switch colors an odd number of times in the code.
It seems to me that update_idletasks isn't working. Is there some way to fix this? I am running python 3.9.5 with Tk 8.6 on Big Sur.
I think what you can do is avoid tasks that will block the mainloop, in this case time.sleep(). So your code can be remade by emulating a for loop with after, and I see nothing that stops this general code from running OS independent:
count = 0 # Think of this as the `_` in for _ in range(9)
def blink(event=None):
global this, that, count
if count < 9: # Basically repeats everytime `count` is less than 9, like a for loop
canvas.itemconfigure(this, fill='red')
canvas.itemconfigure(that, fill='blue')
this, that = that, this
count += 1 # Increase count
root.after(400,blink) # Repeat this code block every 400 ms or 0.4 seconds
else:
count = 0 # After it is 9, set it to 0 for the next click to be processed
I found that using update instead of update_idletasks works on both platforms. It's my understanding though, that the latter is much preferred. See the accepted answer to this question for example. This solves my immediate problem, but does anyone know if update_idletasks ever works on the Mac?
I'm new to programming in LUA, although I've learned similar languages like JS. It's frustrating if I have to alter the same script in many parts in a group by replacing each script, and I don't know of an elegant way to do it. Instead, I decided to nest all the parts inside of the script. I've seen some examples and I've tried to adapt some of them, but they don't exactly apply to what I want to do and I can't get them to work.
In essence, what I'm trying to do is monitor all the bricks for a player to contact them. I took the original disappearing brick script that was nested inside each brick and modified it. If a part (brick) is touched, that should call the onTouch function, which will make the brick's transparency decrease over time until the in pairs loop is done, after which the brick disappears and CanCollide is turned off. After 2 seconds, it then returns back to normal. I think the problem is with the coding I used to monitor the parts as I don't really understand the right way to monitor multiple objects. Can someone please help? Thanks!
File structure:
function onTouched(brick)
local delay = .1 -- the delay between each increase in transparency (affects speed of disappearance)
local RestoreDelay = 2 -- delay before the brick reappears
local inc = .1 -- how much the brick disappears each time
-- All characters have a Humanoid object
-- if the model has one, it is a character
local h = script.Child:findFirstChild("Humanoid") -- Find Humanoids in whatever touched this
if (h ~=nil) then -- If there is a Humanoid then
h.Health = h.MaxHealth -- Set the health to maximum (full healing)
for x=0,1, inc do
script.Child.Transparency = x+inc
script.Child.CanCollide = true
wait(delay)
end
wait(delay)
script.Child.Transparency = 1
script.Child.CanCollide = false
wait(RestoreDelay)
script.Child.Transparency = 0
script.Child.CanCollide = true
else
end
end
while true do
local bricks=script:GetChildren():IsA("basic.part")
for x=1,brick in pairs(bricks) do
brick.Touched:connect(onTouched(brick)) -- Make it call onTouched when touched
end
end
end
For the most part, you've gotten it right, but you've got a few syntax errors where there are different conventions between JavaScript and Lua.
In JS, you would fetch an array of objects and then bee able to filter it immediately, but in Lua, there is limited support for that. So a JavaScript line like :
var bricks = script.GetChildren().filter(function(item) {
return item === "basic.part"
})
cannot be done all in one line in Lua without assistance from some library. So you'll need to move the check into the loop as you iterate over the objects.
Other than that, the only other thing to change is the onTouched handler's function signature. The BasePart.Touched event tells you which object has touched the brick, not the brick itself. But by creating a higher order function, it's easy to get access to the brick, and the thing that touched it.
-- create a helper function to access the brick and the thing that touched it
function createOnTouched(brick)
-- keep track whether the animation is running
local isFading = false
return function(otherPart)
-- do not do the animation again if it has already started
if isFading then
return
end
local delay = .1 -- the delay between each increase in transparency (affects speed of disappearance)
local restoreDelay = 2 -- delay before the brick reappears
local inc = .1 -- how much the brick disappears each time
-- All characters have a Humanoid object, check for one
local h = otherPart.Parent:FindFirstChild("Humanoid")
if h then
-- heal the player
h.Health = h.MaxHealth
-- start fading the brick
isFading = true
brick.CanCollide = true
for i = 0, 1, inc do
brick.Transparency = i
wait(delay)
end
-- turn off collision for the brick
wait(delay)
brick.Transparency = 1
brick.Anchored = true
brick.CanCollide = false
-- turn the part back on
wait(restoreDelay)
brick.Transparency = 0
brick.CanCollide = true
-- reset the animation flag
isFading = false
end
end
end
-- loop over the children and connect touch events
local bricks = script:GetChildren()
for i, brick in ipairs(bricks) do
if brick:IsA("BasePart") then
local onTouchedFunc = createOnTouched(brick)
brick.Touched:Connect(onTouchedFunc)
end
end
I've just installed the new MATLAB R2013b for 64bit Mac, and my OS is OS X 10.8.4. I'm running into a consistent problem that I never had with R2013a. When I run one of my scripts (see below), the entire script goes through OK, but then I keep getting an error message "MATLAB has encountered an internal problem and needs to close." Then I have to shut MATLAB down.
I have a feeling that I've goofed somewhere on the installation since I'm new to MATLAB, but I'm not sure.
This exact same script still runs fine on R2013a, which I've yet to uninstall. The script (making use of Psychtoolbox) is an experiment which opens a screen, presents some text, presents an audio file, and requires the participant to respond with 6 keystrokes. This script only presents two audio files, since I'm just testing it.
All the loops seem to work on both versions of MATLAB, and the screen closes at the end (which only happens after 2 passes through the main loop). I take this to mean the script is working, but something in a post stage is causing issues.
Any and all ideas are much appreciated!
-Josh
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%% SCREEN & AUDIO SETUP %%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%
%% SCREEN %%
%%%%%%%%%%%%
% Set up a nice blank screen.
whichScreen = 0;
% Full Screen mode
%window = Screen(whichScreen, 'OpenWindow');
% Small screen mode used for code testing
window = Screen('OpenWindow',0, [450 450 500], [5,5, 550,550]);
white = WhiteIndex(window); % pixel value for white
Screen(window, 'FillRect', white);
Screen(window, 'Flip');
% Set global text size for the display.
Screen('TextSize', window, 15);
Screen(window,'TextFont','Arial');
Screen('TextStyle', window, 0)
%%%%%%%%%%%
%% AUDIO %%
%%%%%%%%%%%
% Set initial audio parameters:
nrchannels = 1; % All stimuli are mono-sounds.
freq = 44100;
% Initialize sound driver.
InitializePsychSound;
try
pahandle = PsychPortAudio('Open', [], [], 3, freq, nrchannels);
catch
% If the above fails, use the audio device's standard frequency.
psychlasterror('reset'); % I believe this some reseting of the error made in 'try'.
pahandle = PsychPortAudio('Open', [], [], 3, [], nrchannels);
end
%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%
%%%%% MAIN LOOP %%%%%
%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%
home = '/Users/josh/Dropbox/Beverlab/Fall_2013_Study/Design/Matlab/'
SampleExperiment = {strcat(home,'Stimuli/tokensA/gipa_mono.wav'),...
strcat(home,'Stimuli/tokensB/gabo_mono.wav')};
timeLimit = 10; % Set up the time limit.
ans = 0; % This is used to track whether or not the participant answered.
numStim = 2; % Just using 2 right now to test the code
ListenChar(0);
for i=1:numStim;
token = char(SampleExperiment(1,randi([1,2]))); % randomly select a wave file from 'SampleExperiment' and assign it to 'token'
[y,freq] = wavread(token); % Read the current wav file.
wavedata = y'; % Transpose wav data.
PsychPortAudio('FillBuffer', pahandle, wavedata); % fill the buffer, ready to play
t1 = PsychPortAudio('Start', pahandle, 1, 0, 1); % play the wave file and get timestamp in one go
while GetSecs<t1+timeLimit
if ans<6
[secs, keyCode, deltaSecs] = KbWait([],2,t1+timeLimit);
if isempty(find(keyCode,1))
break
end
if ~isempty(find(keyCode,1))
ans=ans+1;
end
end
if ans==6
WaitSecs(rand*3+1);
break
end
end
if ans<6
DrawFormattedText(window, 'Lets try that again...press 6 times', 'center', 'center');
Screen(window, 'Flip');
WaitSecs(1);
Screen(window, 'FillRect', white);
Screen(window, 'Flip');
[y,freq] = wavread(token); % Read the current wav file.
wavedata = y'; % Transpose wav data.
PsychPortAudio('FillBuffer', pahandle, wavedata); % fill the buffer, ready to play
t1 = PsychPortAudio('Start', pahandle, 1, 0, 1); % play the wave file and get timestamp in one go
while GetSecs<t1+timeLimit
if ans<6
[secs, keyCode, deltaSecs] = KbWait([],2,t1+timeLimit);
if isempty(find(keyCode,1))
break
end
if ~isempty(find(keyCode,1))
ans=ans+1;
end
end
if ans==6
WaitSecs(rand*3+1);
break
end
end
end
end
Screen('CloseAll')
This sort of error usually indicates something drastic and unrecoverable has happened. It appears that the Psychtoolbox contains MEX files, that is probably the most likely culprit. I would either attempt to rebuild those using R2013b, or contact the authors to see if they have a version compatible with R2013b.
This crashing is likely due to a new bug in OSX 10.8.4, causing PsychToolBox to crash on closing the connection to the display server (and apparently bringing MATLAB with it). See here for discussion and resolution.
Anybody still having this issue, please update to the latest version of PsychToolBox (which is always a good idea!)
This question already has an answer here:
How to create movies on each generation of a for loop in Matlab plot
(1 answer)
Closed 9 years ago.
I have the following code:
figure;
contour(X1,X2,f);
hold on
plot(top(1:size(top,1)), 'rx');
EDIT
figure;
for i = 1: G
contour(X1,X2,f);
hold on
plot(top(1:size(top,1)), 'rx');
end
NB: G is the maximum generation.
This is supposed to plot contours of sphere superimposed with selected individuals. In each iteration of the individuals, the best individuals is selected and these going on until the global optimum is reached. I need to show this in a movie form as shown in this below:
When you runs each stage of the iteration is indicated in the slides attached. This is what i am trying to do. Any idea please?
OK, I am just copying and pasting now, from here.
However I added FrameRate (per second) since you might want to use (or ask) it later.
writerObj = VideoWriter('Your_video.avi');
writerObj .FrameRate = 1; % 1 frames per second animation.
open(writerObj);
fig_h = figure;
for i = 1: G
contour(X1,X2,f);
hold on
plot(top(1:size(top,1)), 'rx');
frame = getframe(fig_h); % or frame = getframe; since getframe gets gcf.
writeVideo(writerObj, frame);
end
close(writerObj);
Now you will have a Your_video.avi file in your working directory.
If VideoWriter is not supported by your matlab, you could use use avifile same as mentioned in this answer (or in mathwork documentaion example here) like this:
aviobj = avifile('Your_video.avi','compression','None', 'fps', 1);
fig_h = figure;
for i = 1:G
contour(X1,X2,f);
hold on
plot(top(1:size(top,1)), 'rx');
frame = getframe(fig_h); % or frame = getframe; since getframe gets gcf.
aviobj = addframe(aviobj, frame);
end
aviobj = close(aviobj);
EDIT
A problem may occur as pointed out by this question also, which is the captured frame is a constant image. If you are running Matlab on windows, this problem may be caused by conjunction of windows in with certain graphics drivers, and may be solved as mentioned in this answer.
I am using matlab2011 for parallel calculation with multiple cores, which in my code is simply implemented with the block SPMD END. However, for some times, I want to turn off the spmd in the program based on the input parameter. I try the following code, but it doesn't work
if (switchSpmdOn)
spmd
end
% here I put my code for calculation in parallel or series
if (switchSpmdOn)
end % this end is used to close the spmd block
end
I am wondering if there is anything like marco to turn off spmd in the code.
You can pass the number of workers as a parameter to spmd. If the number of workers specified is 0, i.e.,
spmd(0)
statement; %# block body
end
then MATLAB will execute the block body locally and create Composite objects, the same as if there is no pool available.
Example
switchSpmdOn = true;
%# set the number of workers
if (switchSpmdOn)
workers = 3;
matlabpool(workers);
else
workers = 0;
end
%# application. if 'workers' is 0, MATLAB will execute this code locally
spmd (workers)
%# build magic squares in parallel
q = magic(labindex + 2);
end
for ii=1:length(q)
% plot each magic square
figure, imagesc(q{ii});
end
if (switchSpmdOn)
matlabpool close
end