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Difference between two lists
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Using Except is exactly the right way to go. If your type overrides Equals and GetHashCode, or you're only interested in reference type equality (i.e. two references are only "equal" if they refer to the exact same object), you can ...
Scala underscore - ERROR: missing parameter type for expanded function
... there have been quite a few questions on this, but I've created a simple example that I thought should work,but still does not and I'm not sure I understand why
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Not equal != operator on NULL
Could someone please explain the following behavior in SQL?
11 Answers
11
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Force line-buffering of stdout when piping to tee
...her words, as long as your printf argument ends with a newline, you can expect the line to be printed instantly. This does not appear to hold when using a pipe to redirect to tee .
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Python multiprocessing PicklingError: Can't pickle
I am sorry that I can't reproduce the error with a simpler example, and my code is too complicated to post. If I run the program in IPython shell instead of the regular Python, things work out well.
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Javascript Thousand Separator / string format [duplicate]
... answer below was wrong. There is a built in function for this, which is exactly what kaiser suggests below: toLocaleString
So you can do:
(1234567.89).toLocaleString('en') // for numeric input
parseFloat("1234567.89").toLocaleString('en') // for string input
The function implemen...
Are Javascript arrays sparse?
That is, if I use the current time as an index into the array:
7 Answers
7
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sed in-place flag that works both on Mac (BSD) and Linux
...tion of sed todo in-place editing without backups that works both on Linux and Mac? While the BSD sed shipped with OS X seems to need sed -i '' … , the GNU sed Linux distributions usually come with interprets the quotes as empty input file name (instead of the backup extension), and needs ...
A numeric string as array key in PHP
... the value with a string key doesn't work, though. Add this line to your example: echo $data['12'];. It will give the error, "Notice: Undefined offset: 12 in - on line 5".
– L S
May 29 '16 at 9:47
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Dynamically select data frame columns using $ and a character value
...different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic subset of cols , ne...