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pip issue installing almost any library
... new to coding, so I thought maybe this is something I've been doing wrong and have opted out to easy_install to get most of what I needed done, which has generally worked. However, now I'm trying to download the nltk library, and neither is getting the job done.
...
Calling shell functions with xargs
...xargs -n 1 -P 10 -I {} bash -c 'echo_var "$@"' _ {}
Also, using return 0 and exit 0 like that masks any error value that might be produced by the command preceding it. Also, if there's no error, it's the default and thus somewhat redundant.
@phobic mentions that the Bash command could be simplifi...
Visual Studio 64 bit?
...rmance perspective the pointers get larger, so data
structures get larger, and the processor cache stays the same size.
That basically results in a raw speed hit (your mileage may vary). So
you start in a hole and you have to dig yourself out of that hole by
using the extra memory above 4G to your ...
Asynchronous method call in Python?
...multiprocessing module added in Python 2.6. You can use pools of processes and then get results asynchronously with:
apply_async(func[, args[, kwds[, callback]]])
E.g.:
from multiprocessing import Pool
def f(x):
return x*x
if __name__ == '__main__':
pool = Pool(processes=1) ...
How do I shutdown, restart, or log off Windows via a bat file?
...
The most common ways to use the shutdown command are:
shutdown -s — Shuts down.
shutdown -r — Restarts.
shutdown -l — Logs off.
shutdown -h — Hibernates.
Note: There is a common pitfall wherein users think -h means "help" (which it does for every other comman...
What does “not run” mean in R help pages?
...isible on help pages, but will
be run both by the package checking tools, and the
'example()' function. This was previously 'testonly', and
that form is still accepted.
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What is the easiest way to duplicate an activerecord record?
... Does this still work in Rails 3.1.0.beta? When I do q = p.clone, and then p == q, I get true back. On the other hand, if I use q = p.dup, I get false back when comparing them.
– Juno Woods
Feb 8 '11 at 2:10
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You can't specify target table for update in FROM clause
...you should only be selecting the columns you need in that innermost query, and adding a good WHERE clause to limit the results, too.
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WPF - How to force a Command to re-evaluate 'CanExecute' via its CommandBindings
I have a Menu where each MenuItem in the hierarchy has its Command property set to a RoutedCommand I've defined. The associated CommandBinding provides a callback for the evaluation of CanExecute which controls the enabled state of each MenuItem .
...
What does an exclamation mark mean in the Swift language?
...ome/None), not the value itself (T). So john isn't an instance of Person, and it doesn't have an apartment member:
john.apartment
// 'Person?' does not have a member named 'apartment'
The actual Person value can be unwrapped in various ways:
"forced unwrapping": john! (gives the Person value i...