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How to implement common bash idioms in Python? [closed]
...s are all aimed at python people who are afraid of (or don't want to spend time learning) bash, am I right?
– Buttle Butkus
Jul 13 '17 at 7:34
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Difference between Fact table and Dimension table?
...with it (Example of dimension tables: Geography, Item, Supplier, Customer, Time, etc.). It would be valid also for the dimension to have a parent, in which case the model is of type "Snow Flake". However, designers attempt to avoid this kind of design since it causes more joins that slow performance...
If my interface must return Task what is the best way to have a no-operation implementation?
... to transform it into a state-machine. It will also create a new task each time you call it. Returning an already completed task would be clearer and more performant.
– i3arnon
Aug 3 '15 at 20:11
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How can I read large text files in Python, line by line, without loading it into memory?
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@rochacbruno, it only reads one line at a time. When the next line is read, the previous one will be garbage collected unless you have stored a reference to it somewhere else
– John La Rooy
Jun 25 '11 at 2:33
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Add column with number of days between dates in DataFrame pandas
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Assuming these were datetime columns (if they're not apply to_datetime) you can just subtract them:
df['A'] = pd.to_datetime(df['A'])
df['B'] = pd.to_datetime(df['B'])
In [11]: df.dtypes # if already datetime64 you don't need to use to_datetime
O...
Is it better to use std::memcpy() or std::copy() in terms to performance?
...strings using all four SHA-2 versions (224, 256, 384, 512), and I loop 300 times. I measure times using Boost.timer. That 300 loop counter is enough to completely stabilize my results. I ran the test 5 times each, alternating between the memcpy version and the std::copy version. My code takes advant...
C++ templates Turing-complete?
I'm told that the template system in C++ is Turing-complete at compile time. This is mentioned in this post and also on wikipedia .
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Is there any way to kill a Thread?
..._request flag that each threads checks on regular interval to see if it is time for it to exit.
For example:
import threading
class StoppableThread(threading.Thread):
"""Thread class with a stop() method. The thread itself has to check
regularly for the stopped() condition."""
def __...
Clean way to launch the web browser from shell script?
... major OS's as well as checking to ensure that a URL is passed in as a run-time variable:
#!/bin/bash
if [ -z $1 ]; then
echo "Must run command with the url you want to visit."
exit 1
else
URL=$1
fi
[[ -x $BROWSER ]] && exec "$BROWSER" "$URL"
path=$(which xdg-open || which gnome-open)...
What is the difference between 'log' and 'symlog'?
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I finally found some time to do some experiments in order to understand the difference between them. Here's what I discovered:
log only allows positive values, and lets you choose how to handle negative ones (mask or clip).
symlog means symmetr...