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get list from pandas dataframe column
...rame columns are Pandas Series when you pull them out, which you can then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], inde...
Error: Jump to case label
...code, if foo equals 1, everything is ok, but if it equals 2, we'll accidentally use the i variable which does exist but probably contains garbage.
switch(foo) {
case 1:
int i = 42; // i exists all the way to the end of the switch
dostuff(i);
break;
case 2:
dostuff(i*2); // i is ...
How To Create Table with Identity Column
...TH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON)
) ON [PRIMARY]
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Is Java “pass-by-reference” or “pass-by-value”?
...
Java is always pass-by-value.
Unfortunately, we never handle an object at all, instead juggling object-handles called references (which are passed by value of course). The chosen terminology and semantics easily confuse many beginners.
It goes like this:
public static void main(String[] args) {
...
How can I safely encode a string in Java to use as a filename?
...m with escape sequences.
The reverse of the above encoding should be equally straight-forward to implement.
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Combining node.js and Python
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We are highly concerned about speed, what is the most elegant way how to call a Python "worker" from node.js in an asynchronous non-blocking way?
...
Disable ALL CAPS menu items in Visual Studio 2013
...l Studio 2013 (as in VS 2012), MS reinforced their design decision to make ALL CAPS MENU ITEMS the default. The methods for reverting the menu style are almost the same methods used for Visual Studio 2012, which has been discussed before.
Update (after Visual Studio 2013 Update 4)
As of Visual Stu...
How to trigger event when a variable's value is changed?
...e you want to create a property.
public int MyProperty
{
get { return _myProperty; }
set
{
_myProperty = value;
if (_myProperty == 1)
{
// DO SOMETHING HERE
}
}
}
private int _myProperty;
This allows you to run some code any time the pr...
When to use in vs ref vs out
...ss you need ref.
It makes a big difference when the data needs to be marshalled e.g. to another process, which can be costly. So you want to avoid marshalling the initial value when the method doesn't make use of it.
Beyond that, it also shows the reader of the declaration or the call whether the ...
How to return result of a SELECT inside a function in PostgreSQL?
... -- potential ambiguity
END
$func$ LANGUAGE plpgsql;
Call:
SELECT * FROM word_frequency(123);
Explanation:
It is much more practical to explicitly define the return type than simply declaring it as record. This way you don't have to provide a column definition list with eve...