If I check 'measure runs at every step' in Netlogo's Behaviorspace, in the output does Step 0 refer to the state of the simuation just before Go has been pressed? And then Step 1 would be as if Go had been pressed once, and so on?
What Seth said. But note that a "step" can be anything your want and is not linked to your Go button in any way.
https://ccl.northwestern.edu/netlogo/docs/behaviorspace.html :
"The run options dialog lets you select the formats you would like the
data from your experiment saved in. Data is collected for each run or
step, according to the setting of Measure runs at every step option.
In either case, the initial state of the system is recorded, after the
setup commands run but before the go commands run for the first time."
Yes, that's right. Step 0 is after the setup commands have run, but before the go commands have run.
Related
In Dymola, if an error occurs during the simulation, the calculation would be jammed. How could I stop the simulation now? I tried a lot of methods, but the only way that works right now is using the task manager to terminate the Dymola process.
There are multiple ways to stop a stuck simulation in Dymola
The "Stop" button next to the "Simulation" button. The short-cut for this is F12
Create a empty file "stop" (with no extension) in Dymola's working directory.
Within the (Windows) command-window, hitting CTRL-C a different number of times
once: will give you a status of the progress of the integration
twice: will pause the simulation and will give you some online debugging possibilities
three times: stops the simulation (this will sometimes give you more of the result in the plots than using (1.)
Also you will find the sections "Diagnostics for stuck simulation" and "Debug facilities when running a simulation", which corresponds to (3.), in the Dymola Manual (I think it was Volume 2).
I did a standalone application in Matlab and it works. The only problem is that when I launch the application, it takes time before start asking to the user some file (it is the first think the program has to do). The user does not understand if the program is working or not, since no message neither symbol of working progress appear on the screen.
My idea is to show a waitbar until the window asking the file to user appears.
How can I do this? is it possible to use the waitbar outside a loop?
The script starts as follow:
close all
clear all
[filename,pathname] = uigetfile({'*.xlsx'},'Opening File','C:\');
I don't know why, it takes time before open the window for choosing the file.
The time between launch and file selection input appearing is most likely due to the time it takes to load the MCR. You could add a splash screen to your compilation.
If the end user is running from a command line wrap your exe in a system/shell which writes to the command window that the application is starting.
Your issue is most likely the use of clear all. This makes MATLAB remove all variables (in scope, global and persistent), and compiled scripts from memory, forcing it to recompile and load everything again.
If your purpose is to clear all variables in the current scope, you should be able to increase the initial speed of your script by only running clear instead.
Even faster speed can be achieved if you specify which variables to clear using clear var1 var2 ...
Is there any way to stop the execution of a matlab program from the debugger like ctrl+c does, but then being able to continue execution (like you can in say c#)?
If not, is there any better way to workaround this other than trying to pre-emptively set break points or dbstop statements in your matlab code?
I would like to be able to interrupt a long running simulation to look at the current state and then continue the simulation.
The two options I'm currently using/considering are
dbstop commands (or (conditional) breakpoints) in the code.
Drawback is that sometimes I don't want to stop the simulation for a few hours, sometimes want to stop after only a few seconds (and I don't necessarily know that in advance) and this doesn't work well with this approach: If I set the break condition to break every 5 minutes, I can't leave matlab running for hours without interaction. If I set the condition to higher, I have to wait too long for the condition to hit.
include code to save the workspace every few seconds/minutes and import the workspace into a second matlab instance. Drawback is that this is a huge hassle and also doesn't necessarily allows me to resume the simulation with the state of the saved workspace then step through the code for a few iterations.
I'm hoping there is a better solution than either of the 2. Thanks for any advice!
Edit: I think what I'm going to do is write simple matlab function that checks an environment variable or a file on disk every iteration and calls dbstop if I set a flag in this file or env. This way I can control when (and if needed which of several) the breakpoint hits from outside matlab by editing the file. Messy, but should work.
This is not necessarily the best way, but you could simulate a file-based signal/interrupt framework. It could be done by checking every once in a while inside the long simulation loop for the existence of a specific file. If it does, you enter interactive mode using the keyboard command.
Something along the lines:
CHECK_EVERY = 10; %# like a polling rate
tic
i = 1; %# loop counter
while true %# long running loop
if rem(i,CHECK_EVERY) == 0 && exist('debug.txt','file')
fprintf('%f seconds since last time.\n', toc)
keyboard
tic
end
%# ... long calculations ...
i = i + 1;
end
You would run your simulation as usual. When you would like to step in the code, simply create a file debug.txt (manually that is), and the execution will halt and you get the prompt:
2.803095 seconds since last time.
K>>
You could then inspect your variables as usual... To continue, simply run return (dont forget to temporarily rename or remove the file). In order to exit, use dbquit
EDIT: Just occurred to me, instead of checking for files, an easier solution would be to use a dummy figure as the flag (as long as the figure is open, keep running).
hFig = figure; drawnow
while true
if ~ishandle(hFig)
keyboard
hFig = figure; drawnow
end
%# ...
pause(0.5)
end
With the release of R2016a, you can just hit the Pause button in the code editor and it will halt right away. The keyboard shortcut is Ctrl+F5.
To pause the execution of a program while it is running, in the Editor tab, click the Pause button. MATLAB pauses execution at the next executable line*.
When your code is running, the Start button will turn into a pause:
Another change with this release is the ability to add/remove breakpoints while running. Previously you couldn't do this, apparently.
You can set a conditional breakpoint in the MATLAB Editor. You can also use DBSTOP to do this. For example, this will set a conditional breakpoint in the file myFcn at line 20 which will stop execution when a loop variable i is a multiple of 500:
dbstop in myFcn.m at 20 if rem(i,500) == 0
Then you can continue execution after you inspect some of your variables.
If saving the workspace to a file is a good proxy for what you want, how about making a simple GUI with a toggle button. In your code, check the state of the button. If the button is depressed, save the state, update a static text to reflect time stamp of last save, unpress the button. Optionally, have a conditional breakpoint based on the state of that toggle button.
Here is an alternate solution using the waitinput File Exchange submission.
The advantage is that you can use it from whithin the current session or in cases where it is troublesome to set up a file. Also it won't leave a file behind on the computer.
The downside is there as well unfortunately, you need to wait for the checking moment before you can terminate and it costs a little bit of time.
for t = 1:10
pause(3) %Doing some calculations
str = waitinput('Enter 1 if you want to stop ',5);
if ~isnan(str)
keyboard; % Enter dbcont if you want to continue from here
end
['moving on, it is now: ' datestr(now)]
pause(3) %Doing some more calculations
end
If you want, you can prevent lines being printed to the screen. In this case you need to enter the input at the time the figure window is open (Look in your start bar on windows).
To summarize, the short code that you can put somewhere like a conditional breakpoint would be:
if ~isnan(waitinput('',5))
keyboard;
end
After certain version (I don't know which one exactly):
Windows: Ctrl + F5
Mac: Command + F5 (I guess)
Unix: I am looking for answer too
After 2016a, there is a button for that on the interface too.
I have started running a script on MATLAB that takes days to finish. Usually, if I changed my mind and I don't want wait for it to finish and I get content with the intermediate results, I highlight the command window and press Ctrl-C to break the code.
Now, I have run MATLAB. But its desktop got kinda stuck in the background. When I try to restore the desktop from the toolbar, it does not restore. But I know from the task manager that the process is running and is consuming Memory and CPU performance. So, I am kinda stuck. I don't want to kill the process because I need the intermediate values in the workspace, and I can't open the desktop to break the code using ctrl-c.
Is there any solution? For example, is there any command that can be used in the command prompt to act as ctrl-c for MATLAB?
I am using MATLAB R2012b and Windows 8.
Quick try to fix the recent Problem:
Try ty set a higher priority to matlab.exe in the Task Manager. (Right click -> Priority -> Higher than normal). Then see if you can get the window to front.
Some approaches to avoid this problem in future:
Try to optimize your code. For starters look at: http://de.mathworks.com/help/matlab/matlab_prog/vectorization.html
Use Matlab compiler for faster execution: http://de.mathworks.com/products/compiler/
Include some drawnow commands at stratetic positions in the code. This allows matlab to process the Event Queue and capture ctr-C commands.
Save intermediate results to output files. For example you could write an output file all 30 min with your intermediate results. Easyiest way would be just save(filename). Then a .matfile with all your workspace variables is generated. You can than kill the process in the task manager, without loosing too much results.
This question already has answers here:
Stop and continue execution from debugger possible?
(6 answers)
Closed 6 years ago.
In MATLAB, I'm running some code which takes a while to run. I'd like to pause the code to check on some variable values. Is there a way I can do this without having to re-run the code from the beginning? I don't want to terminate the program; just pause it.
You can halt execution and give a command prompt in two ways of which I am aware:
Putting keyboard in your code where you want to stop.
Setting a breakpoint.
You can resume and stop execution with dbcont and dbquit, respectively. To step forward, use dbstep. dbstack lets you see where you are. There are many more commands. The help page for any of these will give you other suggestions.
As Dennis Jaheruddin has pointed out, dbstop also has several useful features worth trying. In particular is the ability to set conditional and global (any line meeting a criterion) breakpoints via the dbstop if syntax. For example, dbstop if error will break to a debugging command prompt on any error. One suggestion he made, which I now do, is to put dbstop if error into startup.m so that this behavior will be default when you start MATLAB. You may need to create this file in a userpath folder; edit(fullfile(regexp(userpath,'^[^;]*','match','once'),'startup.m')).
One way to achieve what you're looking for would be to use code sections (also known as code cells), where you divide your code into sections divided by lines with two percent signs (%%).
Then, in the editor, you can press ctrl+enter to execute the current code section, and ctrl+up/down to navigate between sections.
Well there is the pause command, but then you cannot check for the variable contents in the workspace because the program is running.
What you probably want is to set a breakpoint (See the Debug menu / key F12).
At a breakpoint matlab pauses the program and enters debugging mode in which you can see and edit the variables. Once finished, you can resume the program where it was paused.
I'm not sure about Windows users but if you're running Linux you can start Matlab in a terminal using
matlab -nodesktop
then once Matlab has started, cd to your project directory and start your Matlab script. Now whenever you want to pause execution you can use ctrl-Z. Then to resume type fg. I hope this helps.