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How to extract the year from a Python datetime object?
...ew times and you'll be prompted with the members of the "now" object:
now.__add__ now.__gt__ now.__radd__ now.__sub__ now.fromordinal now.microsecond now.second now.toordinal now.weekday
now.__class__ now.__hash__ ...
Why do people say there is modulo bias when using a random number generator?
...o-random number generator which chooses a natural number between 0 and RAND_MAX, which is a constant defined in cstdlib (see this article for a general overview on rand()).
Now what happens if you want to generate a random number between say 0 and 2? For the sake of explanation, let's say RAND_MAX ...
How to import multiple .csv files at once?
...olutions in other answers using things like do.call(rbind,...), dplyr::bind_rows() or data.table::rbindlist().
If you really want each data frame in a separate object, even though that's often inadvisable, you could do the following with assign:
temp = list.files(pattern="*.csv")
for (i in 1:lengt...
Comma in C/C++ macro
...ose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remains parenthesized inside the macro expansion, which prevents it being read as a type in most contexts.
A nice trick to workaround this is that in C++, you can extract a typ...
Output to the same line overwriting previous output?
...
Here's code for Python 3.x:
print(os.path.getsize(file_name)/1024+'KB / '+size+' KB downloaded!', end='\r')
The end= keyword is what does the work here -- by default, print() ends in a newline (\n) character, but this can be replaced with a different string. In this case, endi...
Downloading Java JDK on Linux via wget is shown license page instead
...e.com/otn-pub/java/jdk/14.0.1+7/664493ef4a6946b186ff29eb326336a2/jdk-14.0.1_linux-x64_bin.rpm -O ~/Downloads/jdk-14.0.1_linux-x64_bin.rpm
PS: Alf added this ( me ) :-) this, I couldn't figured out how to just commented at the end... Enjoy it.
UPDATED FOR Oracle JDK 11
wget --no-check-certificate -c...
Bidirectional 1 to 1 Dictionary in C#
...gt;, IDictionary
{
private readonly IDictionary<TFirst, TSecond> _firstToSecond = new Dictionary<TFirst, TSecond>();
[NonSerialized]
private readonly IDictionary<TSecond, TFirst> _secondToFirst = new Dictionary<TSecond, TFirst>();
[NonSerialized]
private r...
Reimport a module in python while interactive
...from the importlib library instead:
import importlib
importlib.reload(some_module)
If you are using python 3.2 or 3.3 you should:
import imp
imp.reload(module)
instead. See http://docs.python.org/3.0/library/imp.html#imp.reload
If you are using ipython, definitely consider using the autor...
MySQL, Check if a column exists in a table with SQL
...LIKE 'fieldname';
With PHP it would be something like...
$result = mysql_query("SHOW COLUMNS FROM `table` LIKE 'fieldname'");
$exists = (mysql_num_rows($result))?TRUE:FALSE;
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How to read a (static) file from inside a Python package?
...he other answers]
import os, mypackage
template = os.path.join(mypackage.__path__[0], 'templates', 'temp_file')
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