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Pandas: drop a level from a multi-level column index?
... If the index you are trying to drop is on the left (row) side and not the top (column) side, you can change "columns" to "index" and use the same method: >>> df.index = df.index.droplevel(1)
– Idodo
Nov 28 '18 at 12:13
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Fastest way to get the first object from a queryset in django?
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Use the convenience methods .first() and .last():
MyModel.objects.filter(blah=blah).first()
They both swallow the resulting exception and return None if the queryset returns no objects.
These were added in Django 1.6, which was released in Nov 2013.
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What is the difference between “Form Controls” and “ActiveX Control” in Excel 2010?
...two kind of controls that can be inserted into a document: Form Controls and ActiveX Controls .
4 Answers
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Heroku free account limited?
... see Heroku provides free account features, but I don't see any detail on bandwidth, disk spaces, requests?
4 Answers
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How to drop SQL default constraint without knowing its name?
...ver, I know the query to check if a default constraint exists for a column and drop a default constraint is:
14 Answers
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How do I detect a click outside an element?
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This breaks standard behaviour of many things, including buttons and links, contained within #menucontainer. I am surprised this answer is so popular.
– Art
Jun 12 '10 at 8:00
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Difference between declaring variables before or in loop?
...etter, a or b?
From a performance perspective, you'd have to measure it. (And in my opinion, if you can measure a difference, the compiler isn't very good).
From a maintenance perspective, b is better. Declare and initialize variables in the same place, in the narrowest scope possible. Don't leave...
JavaScript data grid for millions of rows [closed]
...s set to the total height of all the rows. The rows are still being added and removed as the user is scrolling, but the scrolling itself is done by the browser. That allows it to be very fast yet smooth (onscroll events are notoriously slow). The caveat is that there are bugs/limits in the browse...
What's the most efficient way to test two integer ranges for overlap?
Given two inclusive integer ranges [x1:x2] and [y1:y2], where x1 ≤ x2 and y1 ≤ y2, what is the most efficient way to test whether there is any overlap of the two ranges?
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How do you share constants in NodeJS modules?
...lobal scope with global.FOO = 5. Then you simply need to require the file, and not even save your return value.
But really, you shouldn't do that. Keeping things properly encapsulated is a good thing. You have the right idea already, so keep doing what you're doing.
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