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Python != operation vs “is not”
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@viksit. None has few methods and almost no attributes. If your __eq__ test expected a method or attribute, it might break. def __eq__( self, other ): return self.size == other.size. For example, will break if other happens to be None.
– S.Lott
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How to select rows from a DataFrame based on column values?
... 2 4
4 foo two 4 8
6 foo one 6 12
7 foo three 7 14
If you have multiple values you want to include, put them in a
list (or more generally, any iterable) and use isin:
print(df.loc[df['B'].isin(['one','three'])])
yields
A B C D
0 foo one 0 0
1 bar o...
How do I check if the mouse is over an element in jQuery?
...e return value to data in the object. Then onmouseover, cancel the timeout if there is a value in the data.
Remove the data on callback of the fadeout.
It is actually less expensive to use mouseenter/mouseleave because they do not fire for the menu when children mouseover/mouseout fire.
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How to find current transaction level?
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Run this:
SELECT CASE transaction_isolation_level
WHEN 0 THEN 'Unspecified'
WHEN 1 THEN 'ReadUncommitted'
WHEN 2 THEN 'ReadCommitted'
WHEN 3 THEN 'Repeatable'
WHEN 4 THEN 'Serializable'
WHEN 5 THEN 'Snapshot' END AS TRANSACTION_ISOLATION_LEVEL
FROM sys.dm_exec_sessions
where session_id ...
How can I change the color of pagination dots of UIPageControl?
...ed UIView that uses Core Graphics to render the dots in the colors you specify.
You use the exposed properties to customize and control it.
If you want to you can register a delegate object to get notifications when the user taps on one of the little page dots. If no delegate is registered then th...
Clean ways to write multiple 'for' loops
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The first thing is that you don't use such a data structure. If
you need a three dimensional matrix, you define one:
class Matrix3D
{
int x;
int y;
int z;
std::vector<int> myData;
public:
// ...
int& operator()( int i, int j, int k )
{
re...
How do I import an SQL file using the command line in MySQL?
... .sql file with an export from phpMyAdmin . I want to import it into a different server using the command line.
49 Answe...
Twitter Bootstrap 3: how to use media queries?
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Bootstrap 3
Here are the selectors used in BS3, if you want to stay consistent:
@media(max-width:767px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}
Note: FYI, this may be useful for debugging:
<span class="visible-xs">SIZE XS&...
Python __str__ and lists
In Java, if I call List.toString(), it will automatically call the toString() method on each object inside the List. For example, if my list contains objects o1, o2, and o3, list.toString() would look something like this:
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What's a standard way to do a no-op in python?
I often find myself writing if / elif / else constructs in python, and I want to include options which can occur, but for which the corresponding action is to do nothing. I realise I could just exclude those if statements, but for readability I find it helps to include them all, so that if you are l...