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NumPy or Pandas: Keeping array type as integer while having a NaN value
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This capability has been added to pandas (beginning with version 0.24):
https://pandas.pydata.org/pandas-docs/version/0.24/whatsnew/v0.24.0.html#optional-integer-na-support
At this point, it requires the use of extension dtype Int64 (capitalized), rather than the default dtype int64 (lowe...
Looping through array and removing items, without breaking for loop
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edited Dec 8 '17 at 17:03
community wiki
4 r...
Javascript regex returning true.. then false.. then true.. etc [duplicate]
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/^[^-_]([a-z0-9-_]{4,20})[^-_]$/gi;
You're using a g (global) RegExp. In JavaScript, global regexen have state: you call them (with exec, test etc.) the first time, you get the first match in a given string. Call them again and you get...
Performant Entity Serialization: BSON vs MessagePack (vs JSON)
...:2} is stored in a file and you want to update the value of "a" from 1 to 2000.
With MessagePack, 1 uses only 1 byte but 2000 uses 3 bytes. So "b" must be moved backward by 2 bytes, while "b" is not modified.
With BSON, both 1 and 2000 use 5 bytes. Because of this verbosity, you don't have to move...
How do I check in SQLite whether a table exists?
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1045
I missed that FAQ entry.
Anyway, for future reference, the complete query is:
SELECT name FR...
Gradient borders
...webkit-border-image: -webkit-gradient(linear, left top, left bottom, from(#00abeb), to(#fff), color-stop(0.5, #fff), color-stop(0.5, #66cc00)) 21 30 30 21 repeat repeat;
Prooflink -- http://www.webkit.org/blog/1424/css3-gradients/
Browser support: http://caniuse.com/#search=border-image
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Positioning a div near bottom side of another div
...Chrome 1, and IE 6, 7 and 8:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html><body>
<div style='background-color: yellow; width: 70%;
height: 100px; position: relative;'>
Outer
<div...
Calculate last day of month in JavaScript
If you provide 0 as the dayValue in Date.setFullYear you get the last day of the previous month:
20 Answers
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What is “point free” style (in Functional Programming)?
...you specify the arguments explicitly):
sum (x:xs) = x + (sum xs)
sum [] = 0
Point-free (sum doesn't have any explicit arguments - it's just a fold with + starting with 0):
sum = foldr (+) 0
Or even simpler: Instead of g(x) = f(x), you could just write g = f.
So yes: It's closely related to c...
How to iterate a loop with index and element in Swift
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Yes. As of Swift 3.0, if you need the index for each element along with its value, you can use the enumerated() method to iterate over the array. It returns a sequence of pairs composed of the index and the value for each item in the array. For...