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Check if element exists in jQuery [duplicate]
...ntuitive. The length property tells you how many elements match the query. What is not intuitive or straight-forward about that?
– Alice Wonder
Nov 7 '16 at 21:01
1
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How can I replace a newline (\n) using sed?
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sed is intended to be used on line-based input. Although it can do what you need.
A better option here is to use the tr command as follows:
tr '\n' ' ' < input_filename
or remove the newline characters entirely:
tr -d '\n' < input.txt > output.txt
or if you have the GNU ver...
Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...implementations if we are talking about only a dozen threads (this is also what Raymond Chen suggests on the MSDN blog post Does Windows have a limit of 2000 threads per process?).
On Windows using unbuffered file I/O means that writes must be of a size which is a multiple of the page size. I have ...
How can I force division to be floating point? Division keeps rounding down to 0?
...ce c to be a floating point number in Python in the following?
c = a / b
What is really being asked here is:
"How do I force true division such that a / b will return a fraction?"
Upgrade to Python 3
In Python 3, to get true division, you simply do a / b.
>>> 1/2
0.5
Floor division, the ...
git - Find commit where file was added
...ndy alias for this, because I always forget it:
git config --global alias.whatadded 'log --diff-filter=A'
This makes it as simple as:
git whatadded -- foo.js
The below one liner will recursively search through sub directories of the $PWD for foo.js without having to supply and absolute or re...
How to make good reproducible pandas examples
...ly to above)
In [3]: iwantthis
Out[3]:
A B
0 1 5
1 4 6
Explain what the numbers come from: the 5 is sum of the B column for the rows where A is 1.
do show the code you've tried:
In [4]: df.groupby('A').sum()
Out[4]:
B
A
1 5
4 6
But say what's incorrect: the A column is in the...
ASP.NET MVC 3 Razor - Adding class to EditorFor
...operty,
new { htmlAttributes = new { @class = "MyCssClass" } })
See: What's New in ASP.NET MVC 5.1, Bootstrap support for editor templates
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Chained method calls indentation style in Python [duplicate]
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Raymond, what's the reason Python doesn't allow new line before and after a dot? This makes good formatting harder not easier...
– Piotr Dobrogost
Apr 1 '13 at 18:45
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Listing each branch and its last revision's date in Git
...obsolescent backtick syntax.
(I illustrated that point in 2014 with "What is the difference between $(command) and `command` in shell programming?")
Don't read lines with for.
Probably switch to git for-each-ref refs/remote to get remote branch names in machine-readable format
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Postgresql - unable to drop database because of some auto connections to DB
...pid so you'll have to deal with that.
Since you've revoked CONNECT rights, whatever was trying to auto-connect should no longer be able to do so.
You'll now be able to drop the DB.
This won't work if you're using superuser connections for normal operations, but if you're doing that you need to fix t...