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Fastest way to replace NAs in a large data.table
....805 12.301 134.985
system.time(a_andrie = f_andrie(dt1))
Error: cannot allocate vector of size 305.2 Mb
Timing stopped at: 14.541 7.764 68.285
system.time(f_dowle(dt1))
user system elapsed
7.452 4.144 19.590 # EDIT has faster than this
identical(a_gdata, dt1)
[1] TRUE
Note th...
How should I detect unnecessary #include files in a large C++ project?
...a .cpp file, Properties->C/C++->Advanced) that will output a tree of all included files at compile time. This can help in identifying files that shouldn't need to be included.
You can also take a look at the pimpl idiom to let you get away with fewer header file dependencies to make it easie...
Git pull after forced update
... the working tree since <commit> are discarded.
If you want to actually keep whatever changes you've got locally - do a --soft reset instead. Which will update the commit history for the branch, but not change any files in the working directory (and you can then commit them).
Rebase
You ca...
How to fix corrupted git repository?
... have a corrupted local repo, but a trusted remote.
# This script replaces all your history with that of the remote.
# If there is a .git, it is backed up as .git_old, removing the last backup.
# This does not affect your working tree.
#
# This does not currently work with submodules!
# This will ab...
What should I do when 'svn cleanup' fails?
...
When starting all over is not an option...
I deleted the log file in the .svn directory (I also deleted the offending file in .svn/props-base), did a cleanup, and resumed my update.
...
scp or sftp copy multiple files with single command
...lders to multiple remote folders, these examples won't do the job, as they all will scp files to ~ or ./ only.
– aesede
Apr 28 '15 at 17:09
22
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Is there a difference between foreach and map?
...important point to mention (this is particularly true in Scala) is that a call to map does not result in the execution of its underlying logic until when the expected transformed list is summoned. In contrast, foreach's operation is computed immediately.
– solimant
...
CSS media queries: max-width OR max-height
...iting. It's been a good chance to learn myself! Take the time to systematically read though and I hope it will be helpful.
Media Queries
Media queries essentially are used in web design to create device- or situation-specific browsing experiences; this is done using the @media declaration within...
Suppress command line output
... invocation to this:
taskkill /im "test.exe" /f >nul 2>&1
and all will be better.
That works because stdout is file descriptor 1, and stderr is file descriptor 2 by convention. (0 is stdin, incidentally.) The 2>&1 copies output file descriptor 2 from the new value of 1, which wa...
Convert datetime to Unix timestamp and convert it back in python
...m UTC.
If you have, or can upgrade to, Python 3.3 or later, you can avoid all of these problems by just using the timestamp method instead of trying to figure out how to do it yourself. And even if you don't, you may want to consider borrowing its source code.
(And if you can wait for Python 3.4, ...