When using IPython, it's often convenient to see how long your commands take to run by using the %time magic function. When you use this often enough, you start to wish that you could just get toggle a setting to get this metadata by default whenever you enter a query. Psql lets you do this with \timing. GHCi lets you do this with :set s+. Does IPython let you do this? And if not, why not?
The "ipythonic" way of timing code is using the %timeit or %%timeit magic function (respectively for online, and multi-line code).
These functions provide quite accurate results by running the code multiple times (the exact number is adaptive if not specified).
The global flag you are asking does not exist in ipython. Furthermore, just adding %%timeit to all the cells will not work because global variables are not modified when calling %%timeit. This "feature" is directly inherited from the timeitmodule.
For more info see this ipython issue.
Related
So I'm writing Python with IDLE and my usual workflow is to have two windows (an editor and a console), and run my script with F5 to quickly test it.
My script has some non-optional command line parameters, and I have two conflicting desires:
If someone launches my script without passing any parameters, I'd like him to get an error telling him to do so (argparse does this well)
When I hit F5 in IDLE, I'd like to have my script run with dummy parameters (and I don't want to have more keystrokes than F5 to have this work, and I don't want to have a piece of code I have to remember to remove when I'm not debugging any more)
So far my solution has been that if I get no parameters, I look for a params.debug file (that's not under source control), and if so, take that as default params, but it's a bit ugly... so would there be a cleaner, more "standard" solution to this? Do other IDEs offer easier ways of doing this?
Other solutions I can think of: environment variables, having a separate "launcher" script that's the one taking the "official" parameters.
(I'm likely to try out another IDE anyway)
With some editors you can define the 'execute' command,
For example with Geany, for Python files, F5 is python2.7 %f. That could be modified to something like python2.7 %f dummy parameters. But I use an attached terminal window and its line history more than F5 like commands.
I'm an Ipython user, so don't remember much about the IDLE configuration. In Ipython I usually use the %run magic, which is more like invoking the script from a shell than from an IDE. Ipython also has a better previous line history than the shell.
For larger scripts I like to put the guts of the code (classes, functions) in one file, and test code in the if __name__ block. The user interface is in another file that imports this core module.
Thanks for your question. I also searched for a way to do this. I found that Spyder which is the IDE I use has an option under Run/Configure to enter the command line parameters for running the program. You can even configure different ones for the different editors you have open.
Python tracker issue 5680 is a proposal to add to Idle a way to set command lines args for F5 Run module. You are free to test any of the proposed patches if you are able to apply them.
In the meanwhile conditionally extending sys.argv as done below should fulfill your requirements.
import sys
in __name__ == '__main__':
if 'idlelib.PyShell' in sys.modules:
sys.argv.extend(('a', '-2')) # add your argments here.
print(sys.argv) # in use, parse sys.argv after extending it
# ['C:\\Programs\\python34\\tem.py', 'a', '-2']
I have a lot of if statements throughout my code and was wondering if there is anyway in Matlab to see which if statements are being used when I run my code. I know I could put variables throughout my code and see which ones are being triggered, but I was wondering if there is an easier way. Maybe a built in MATLAB function or something.
Thanks
Type profile viewer in the command line of matlab and execute your code from there. There you can see in the profile report how many times each line is called as well as how long it takes executing the line of code.
More information:
http://www.mathworks.nl/help/matlab/ref/profile.html
http://www.mathworks.nl/help/matlab/matlab_prog/profiling-for-improving-performance.html
To answer precesely to your question, there is a command to log every line the execution is going through. And if you're familiar with unix-like platform, it is the same command: echo. See the Matlab help of echo to see how you can use it. For example, echo on all sets echoing on for all function files.
Besides that, I advise you two things better than analysing the output of echoing a whole script:
look at every warning in the code editor, and apply meaningful corrections.
use the profiler of matlab, as stated in the answer from EJG89, it is indeed a powerful tool!
As described in the manual, ipython is smart enough to automatically strip the default prompt from pasted lines of code -- very handy. I have customized my prompt to my liking, which unfortunately seems to have broken this logic. Is it possible to adapt the pattern match logic in my startup files to reflect a customized prompt, and if so, how?
If you're using the latest IPython (1.0 or the development version), then yes, although it's not something that we particularly support (i.e. the API might change in the future). Define a regex which will match your prompts - like this one for classic Python prompts: re.compile(r'^(>>> ?|\.\.\. ?)').
Then you'll need some code like this (not tested):
from IPython.core.inputtransformer import CoroutineInputTransformer, _strip_prompts
#CoroutineInputTransformer.wrap
def my_prompt():
prompt_re = re.compile(r'foo')
return _strip_prompts(prompt_re)
ip = get_ipython()
ip.input_splitter.physical_line_transforms.insert(0, my_prompt())
ip.input_transformer_manager.physical_line_transforms.insert(0, my_prompt())
You can put that in a startup file (IPYTHONDIR/profile_default/startup/prompts.py) to have it run automatically when you start IPython.
I am optimizing a very time/memory consuming program by running it over a dataset and under multiple parameters. For each "run", I have a csv file, "setup.csv" set up with "runNumber","Command" for each run. I then import this into a perl script to read the command for the run number I would like, extrapolate the variables, then execute it on the system via the system command. Should I be worried about the potential for this to be exploited, (I am worried right now)? If so, what can I do to protect our server? My plan now is to change the file permissions of the "setup.csv" to read only and ownership to root, then go in as root whenever I need to append another run to the list.
Thank you very much for your time.
Run your code in taint mode with -T. That will force you to carefully launder your data. Only pass through strings that are ones you are expecting. Do not launder with .*, but rather check against a list of good strings.
Ideally, there a list of known acceptable values, and you validate against that.
Either way, you want to avoid the shell by using the multi-argument form of system or by using IPC::System::Simple's systemx.
If you can't avoid the shell, you must properly convert the text to pass to the command into shell literals.
Even then, you have to be careful of values that start with -. Lots of tools accept -- to denote the end options, allowing other values to be passed safely.
Finally, you might want to make sure the args don't contain the NUL character (\0).
systemx('tool', '--', #args)
Note: Passing arbitrary strings is not possible in Windows. Extra validation is required.
I never work with the GUI and am always inside a terminal (also full screen, so no title bar) set with the -nodesktop -nodisplay option. I also have different servers that I connect to, to run matlab and each of those have different restrictions on hogging computational resources. Since it's hard to remember which server I'm in,especially if I have multiple sessions open, I was wondering if I could change the prompt to display the server name. Try as I might, I couldn't find a resource that explains how to go about it (I'm beginning to think Mathworks doesn't support it). I know, a workaround would be to simply write a function call to system('hostname') and put the function in the path, so that it's about as easy as typing pwd to find the directory. I'd like to know if there's something more elegant.
There is a submission on the MathWorks File Exchange that can do this for you: setPrompt by Yair Altman. Using it in R2010b, I noticed that I was getting the warning message:
Warning: Possible deprecated use of set on a Java callback.
> In setPrompt at 115
Which I was able to suppress using the warning function like so:
warning('off','MATLAB:hg:JavaSetHGProperty');
And here's how I changed the prompt to the host name using the system function:
>> [~,systemString] = system('hostname');
>> setPrompt([deblank(systemString) '>> ']);
P11-4504>>
The function deblank is used to remove trailing whitespace (in this case a newline) from the string.
NOTE: The above changes (suppressed warning and modified prompt) don't persist after you quit and restart MATLAB, so you could put the above code in your startup.m file to apply them automatically every time you start a new session.