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R memory management / cannot allocate vector of size n Mb
...to a minimum when you need to make objects of this size. Use gc() to clear now unused memory, or, better only create the object you need in one session.
If the above cannot help, get a 64-bit machine with as much RAM as you can afford, and install 64-bit R.
If you cannot do that there are many o...
Worth switching to zsh for casual use? [closed]
... c=vim
Or print the names of files modified today:
print *(e:age today now:)
You can probably do all of these things in bash, but my experience with zsh is that if there's something I want to do, I can probably find it in zsh-lovers.
I also find the book 'From Bash to Z-Shell' really useful.
...
Converting datetime.date to UTC timestamp in Python
...eturn (td.microseconds + (td.seconds + td.days * 86400) * 10**6) / 10**6
now = datetime.utcnow()
print now
print totimestamp(now)
Beware of floating-point issues.
Output
2012-01-08 15:34:10.022403
1326036850.02
How to convert an aware datetime object to POSIX timestamp
assert dt.tzinfo is n...
Unit testing of private methods [duplicate]
... declare your test fixture as a friend to the class under test.
And you know, if testing private functions were unequivocally bad like some of the other answers were saying, then it probably wouldn't be built into Google Test.
You can read more about when testing private functions is good or bad...
How to link to a named anchor in Multimarkdown?
...
@jj1bdx I do now -- the <a id="id"></a> form is best. See this SO question/answer.
– Steve Powell
May 28 '12 at 16:12
...
Saving an Object (Data persistence)
...med _pickle, but doing this is no longer necessary since the pickle module now does it automatically—see What difference between pickle and _pickle in python 3?.
The rundown is you could use something like the following to ensure that your code will always use the C version when it's available in...
Is there a way to change the spacing between legend items in ggplot2?
...
Now that opts is deprecated in ggplot2 package, function theme should be used instead:
library(grid) # for unit()
... + theme(legend.key.height=unit(3,"line"))
... + theme(legend.key.width=unit(3,"line"))
...
How to make a Python script run like a service or daemon in Linux
...ike so:
import os, sys
fpid = os.fork()
if fpid!=0:
# Running as daemon now. PID is fpid
sys.exit(0)
Of course you also need to implement an endless loop, like
while 1:
do_your_check()
sleep(5)
Hope this get's you started.
...
What blocks Ruby, Python to get Javascript V8 speed? [closed]
...mple, for certain operations, Rubinius's Hash class is faster than YARV's. Now, this doesn't sound terribly exciting until you realize that Rubinius's Hash class is implemented in 100% pure Ruby, while YARV's is implemented in 100% hand-optimized C.
So, at least in some cases, Rubinius can generate...
Remove unwanted parts from strings in a column
...ings in a column?
6 years after the original question was posted, pandas now has a good number of "vectorised" string functions that can succinctly perform these string manipulation operations.
This answer will explore some of these string functions, suggest faster alternatives, and go into a ti...