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pandas GroupBy columns with NaN (missing) values
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This is mentioned in the Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [...
Select mySQL based only on month and year
I have a column in my mySQL DB that has some rows. One of this row is a DATE, like this: 2012-02-01
12 Answers
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What key shortcuts are to comment and uncomment code?
... edited Mar 20 '13 at 13:49
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answered Aug 22 '12 at 5:27
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How to format a JavaScript date
...custom-delimited date formats, you have to pull out the date (or time)
components from a DateTimeFormat object (which is part of the
ECMAScript Internationalization API), and then manually create a string
with the delimiters you want.
To do this, you can use DateTimeFormat#formatToParts. You could
d...
How to effectively work with multiple files in Vim
...p to any tab by using ngt, where n is the index of the tab (beginning with one). I think there's an option that displays the index of each tab near the file name, but I don't know what it is. If anyone knows, I'd love to hear it.
– void-pointer
Jan 13 '12 at 2:...
Clear the entire history stack and start a new activity on Android
...d not do that. :)
Edit:
As per @Ben Pearson's comment, for API <=10 now one can use IntentCompat class for the same. One can use IntentCompat.FLAG_ACTIVITY_CLEAR_TASK flag to clear task. So you can support pre API level 11 as well.
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Utils to read resource text file to String (Java) [closed]
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You can use the old Stupid Scanner trick oneliner to do that without any additional dependency like guava:
String text = new Scanner(AppropriateClass.class.getResourceAsStream("foo.txt"), "UTF-8").useDelimiter("\\A").next();
Guys, don't use 3rd party stuff unless...
How to create a fixed-size array of objects
...zed, because assumptions about the content of uninitialized references are one of the ways that programs in C (and some other languages) can become buggy. So, you need to explicitly ask for an [SKSpriteNode?] array that contains 64 nils:
var sprites = [SKSpriteNode?](repeating: nil, count: 64)
Th...
How to get WordPress post featured image URL
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I think this is the easiest solution and the updated one:
<?php the_post_thumbnail('single-post-thumbnail'); ?>
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What are the differences between the threading and multiprocessing modules?
...ance benefit from threading. The same is true if the heavy computation is done by some subprocess that you run and wait on.
More importantly, there are cases where this doesn't matter. For example, a network server spends most of its time reading packets off the network, and a GUI app spends most o...