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When NOT to use yield (return) [duplicate]
...t);
}
}
which still uses yield return, but is much smarter about it. Now we are O(n) in time and O(h) in heap space, and O(1) in stack space.
Further reading: see Wes Dyer's article on the subject:
http://blogs.msdn.com/b/wesdyer/archive/2007/03/23/all-about-iterators.aspx
...
List comprehension vs map
... {x:x**2 for x in rangeNeg5}
)
Efficiency comparison for python3
map is now lazy:
% python3 -mtimeit -s 'xs=range(1000)' 'f=lambda x:x' 'z=map(f,xs)'
1000000 loops, best of 3: 0.336 usec per loop ^^^^^^^^^
Therefore if you will not be using all your data, or do not know ahead of tim...
Redirecting to URL in Flask
...fined If-Modified-Since headers.
New in version 0.6: The location can now be a unicode string that is
encoded using the iri_to_uri() function.
Parameters:
location – the location the response should redirect to.
code – the redirect status code. defaults to 302.
Response (...
Why shouldn't all functions be async by default?
...() was void N() { S(); T(); }, and R and S produce side effects, then you know that R's side effect happens before S's side effect. But if you have async void M() { await Q(); R(); } then suddenly that goes out the window. You have no guarantee whether R() is going to happen before or after S() (unl...
Run an untrusted C program in a sandbox in Linux that prevents it from opening files, forking, etc.?
...t.c root/assignment.c
Exit the VM's root FS:
cd ..
sudo umount mountpoint
Now the image is ready, we just need to run it. It will compile and run the submission after booting.
mkfifo /tmp/guest_output
Open a seperate terminal and start listening for guest output:
dd if=/tmp/guest_output bs=1
In an...
Android accelerometer accuracy (Inertial navigation)
...which would be pretty limiting. No one reads the TOS anyway.
Oh, and you know that INS drifts with the rotation of the earth, right? So there's that too. One hour later and you're mysteriously climbing on a 15° slope into space. That's assuming you had an INS capable of maintaining location that l...
How to export all collections in MongoDB?
...
Please let us know where you have installed your Mongo DB ? (either in Ubuntu or in Windows)
For Windows:
Before exporting you must connect to your Mongo DB in cmd prompt and make sure that you are able to connect to your local host. ...
How to format a floating number to fixed width in Python
...
This has changed in the last 4 years, now % formatting is the oldest method of formatting. For several reasons using str.format or f-strings is preferred over %. Previously when it was only str.format, people had some reasons but f-strings fixed that hole. format...
Numpy: Get random set of rows from 2D array
...mask = numpy.random.choice([False, True], len(data_arr), p=[0.75, 0.25])
Now you can call data_arr[mask] and return ~25% of the rows, randomly sampled.
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node.js remove file
...s.exists. Because according to the latest node.js documentation, fs.exists now deprecated.
For example:-
fs.stat('./server/upload/my.csv', function (err, stats) {
console.log(stats);//here we got all information of file in stats variable
if (err) {
return console.error(err);
}
...