[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.
I'm trying to add a function that randomly selects objects from the table targets. I read somewhere that you can use targets[math.random(#targets)], but when I do that, it doesn't just reset one of the targets regardless of resetTarget() call, and it doesn't actually make the next target random.
local targets -- an array of target objects
local bomb = display.newImage("bomb.png")
local asteroid = display.newImage("asteroid.png")
local balloon = display.newImage("balloon.png")
targets = { bomb, asteroid, balloon }
function createTarget()
for i = 1, #targets do
local t = targets[i]
t.x = WIDTH + 50 -- start slightly off screen to the right
t.y = math.random(100, HEIGHT - 100) -- at random altitude
end
end
function resetTarget(obj)
createTarget()
end
function detectHits()
-- Do hit detection for ball against each target
local HIT_SLOP = BIRD_RADIUS * 2 -- Adjust this to adjust game difficulty
for i = 1, #targets do
local t = targets[i]
if math.abs(t.x - bird.x) <= HIT_SLOP
and math.abs(t.y - bird.y) <= HIT_SLOP then
-- Hit
isBomb(t)
isAsteroid(t)
isBalloon(t)
resetTarget(t)
updateScore()
end
end
end
This will work but you will need a forward reference to currentTarget.
What is your function to target the random target?
local newTarget = function()
local rand = math.random(1,#targets)
currentTarget = target[rand]
doSomething()
end
How do I find all cells containing a text value such as merchant_id and change the background color of those cells to a specific color?
This macro will use the current selected range and check each cell for merchant_id. Then mark it maroon if true. To pick a particular color, the best way is to record a macro and see what values it creates. Take those numbers and replace the contents of the With block
Sub MarkCellsInSelection()
For Each c In Selection
If c.Value = "merchant_id" Then
With c.Interior
.Pattern = xlSolid
.PatternColorIndex = xlAutomatic
.ThemeColor = xlThemeColorAccent2
.TintAndShade = 0.399975585192419
.PatternTintAndShade = 0
End With
End If
Next
End Sub
I would like to create an animation which enables the user to go backward and forward through the steps of simulation.
An animation has to simulate the iterative process of channel decoding (a receiver receives a block of bits, performs an operation and then checks if the block corresponds to parity rules. If the block doesn't correspond the operation is performed again and the process finally ends when the code corresponds to a given rules).
I have written the functions which perform the decoding process and return a m x n x i matrix where m x n is the block of data and i is the iteration index. So if it takes 3 iterations to decode the data the function returns a m x n x 3 matrix with each step is stired.
In the GUI (.fig file) I put a "decode" button which runs the method for decoding and there are buttons "back" and "forward" which have to enable the user to switch between the data of recorded steps.
I have stored the "decodedData" matrix and currentStep value as a global variable so by clicking "forward" and "next" buttons the indices have to change and point to appropriate step states.
When I tried to debug the application the method returned the decoded data but when I tried to click "back" and "next" the decoded data appeared not to be declared.
Does anyone know how is it possible to access (or store) the results of the functions in order to enable the described logic which I want to implement in Matlab GUI?
Ultimately, this is a scoping of variables problem.
Global variables is rarely the right answer.
This video discusses the handles structure in GUIDE:
http://blogs.mathworks.com/videos/2008/04/17/advanced-matlab-handles-and-other-inputs-to-guide-callbacks/
This video discusses sharing of variables between GUIs and could apply to a single GUI problem also.
http://blogs.mathworks.com/videos/2005/10/03/guide-video-part-two/
The trick is to use nested functions so that they share the same workspace. Since I already started with an example in your last question, now I'm simply adding GUI controls to enable going forward/backward interactively, in addition to play/stop the animation:
function testAnimationGUI()
%# coordinates
t = (0:.01:2*pi)'; %# 'fix SO syntax highlight
D = [cos(t) -sin(t)];
%# setup a figure and axis
hFig = figure('Backingstore','off', 'DoubleBuffer','on');
hAx = axes('Parent',hFig, 'XLim',[-1 1], 'YLim',[-1 1], ...
'Drawmode','fast', 'NextPlot','add');
axis(hAx, 'off','square')
%# draw circular path
line(D(:,1), D(:,2), 'Color',[.3 .3 .3], 'LineWidth',1);
%# initialize point
hLine = line('XData',D(1,1), 'YData',D(1,2), 'EraseMode','xor', ...
'Color','r', 'marker','.', 'MarkerSize',50);
%# init text
hTxt = text(0, 0, num2str(t(1)), 'FontSize',12, 'EraseMode','xor');
i=0;
animation = false;
hBeginButton = uicontrol('Parent',hFig, 'Position',[1 1 30 20], ...
'String','<<', 'Callback',#beginButton_callback);
hPrevButton = uicontrol('Parent',hFig, 'Position',[30 1 30 20], ...
'String','<', 'Callback',#previousButton_callback);
hNextButton = uicontrol('Parent',hFig, 'Position',[60 1 30 20], ...
'String','>', 'Callback',#nextButton_callback);
hEndButton = uicontrol('Parent',hFig, 'Position',[90 1 30 20], ...
'String','>>', 'Callback',#endButton_callback);
hSlider = uicontrol('Parent',hFig, 'Style','slider', 'Value',1, 'Min',1,...
'Max',numel(t), 'SliderStep', [10 100]./numel(t), ...
'Position',[150 1 300 20], 'Callback',#slider_callback);
hPlayButton = uicontrol('Parent',hFig, 'Position',[500 1 30 20], ...
'String','|>', 'Callback',#playButton_callback);
hStopButton = uicontrol('Parent',hFig, 'Position',[530 1 30 20], ...
'String','#', 'Callback',#stopButton_callback);
%#----------- NESTED CALLBACK FUNCTIONS -----------------
function beginButton_callback(hObj,eventdata)
updateCircle(1)
end
function endButton_callback(hObj,eventdata)
updateCircle(numel(t))
end
function nextButton_callback(hObj,eventdata)
i = i+1;
if ( i > numel(t) ), i = 1; end
updateCircle(i)
end
function previousButton_callback(hObj,eventdata)
i = i-1;
if ( i < 1 ), i = numel(t); end
updateCircle(i)
end
function slider_callback(hObj, eventdata)
i = round( get(gcbo,'Value') );
updateCircle(i)
end
function playButton_callback(hObj, eventdata)
animation = true;
while animation
i = i+1;
if ( i > numel(t) ), i = 1; end
updateCircle(i)
end
end
function stopButton_callback(hObj, eventdata)
animation = false;
end
function updateCircle(idx)
set(hSlider, 'Value', rem(idx-1,numel(t))+1) %# update slider to match
set(hLine,'XData',D(idx,1), 'YData',D(idx,2)) %# update X/Y data
set(hTxt,'String',num2str(t(idx))) %# update angle text
drawnow %# force refresh
if ~ishandle(hAx), return; end %# check valid handle
end
%#-------------------------------------------------------
end
You might find the slider functionality a bit buggy, but you get the idea :)
When I try to invoke a subfunction in a GUI/GUIDE file (using a function handle which has been exposed as a global variable), a new axes is always created even if I set the axes to a specific axes in the GUIDE figure. Does anyone know why this is happening? GUIDE code is:
###############################################################
function varargout = demo(varargin)
% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name', mfilename, ...
'gui_Singleton', gui_Singleton, ...
'gui_OpeningFcn', #demo_OpeningFcn, ...
'gui_OutputFcn', #demo_OutputFcn, ...
'gui_LayoutFcn', [] , ...
'gui_Callback', []);
if nargin && ischar(varargin{1})
gui_State.gui_Callback = str2func(varargin{1});
end
if nargout
[varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT
function demo_OpeningFcn(hObject, eventdata, handles, varargin)
handles.output = hObject;
% Update handles structure
guidata(hObject, handles);
global myhandles updateFunction;
myhandles = handles;
updateFunction = #update;
function varargout = demo_OutputFcn(hObject, eventdata, handles)
varargout{1} = handles.output;
function pushbutton1_Callback(hObject, eventdata, handles)
update();
function update()
global myhandles;
axes(myhandles.axes1);
plot(1:2,1:2);
###########################################################################
And when I do (outside file above):
global updateFunction;
feval(updateFunction)
I always see the plot in a newly created figure window, not in the GUI figure. Why is this happening?
The first thing I would try is to replace the function update with the following:
function update
global myhandles;
plot(myhandles.axes1,1:2,1:2);
This will explicitly tell the PLOT function to plot into the given axes. If that doesn't work, try setting the axes 'NextPlot' property to 'add' (probably in demo_OpeningFcn):
set(myhandles.axes1,'NextPlot','add');
By default, when you create a GUI using GUIDE, Matlab sets the 'HandleVisibility' property of all objects associated with the GUI to 'callback'. This means that you cannot set these handles to be the current figure or current axis from anywhere outside of the callback routines (ie. from the command line or an external function).
To work around this you can either specify the appropriate handle explicitly in all of your plotting functions or you can set the 'HandleVisibility' property of the axes to 'on'. This can be done on an object by object basis via the property inspector, or for the entire GUI by going to 'Tools -> GUI Options...' and changing the 'Command-line Accessibility:' to 'on'.