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Extract a regular expression match
...nd adds a few that are missing:
library(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1] "12"
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How to check if a process id (PID) exists
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10 Answers
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Where is the WPF Numeric UpDown control?
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50
Simply use the IntegerUpDown control in the xtended wpf toolkit
You can use it like this:
Add ...
Natural Sort Order in C#
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150
The easiest thing to do is just P/Invoke the built-in function in Windows, and use it as the com...
SVG gradient using CSS
...pe-rendering: crispEdges;
fill: url(#MyGradient);
}
<svg width="100" height="50" version="1.1" xmlns="http://www.w3.org/2000/svg">
<style type="text/css">
rect{fill:url(#MyGradient)}
</style>
<defs>
<linearGradient id="MyGradie...
CSS hexadecimal RGBA?
...and 8-digit hexadecimal RGBA notation!
Three weeks ago (18th of December 2014) the CSS Color Module Level 4 editor's draft was submitted to the CSS W3C Working Group. Though in a state which is heavily susceptible to change, the current version of the document implies that in the somewhat near fut...
Run command on the Ansible host
...ou want to run an entire play on the Ansible host, then specify hosts: 127.0.0.1 and connection:local in the play, for example:
- name: a play that runs entirely on the ansible host
hosts: 127.0.0.1
connection: local
tasks:
- name: check out a git repository
git: repo=git://foosball.exa...
How to reuse an ostringstream?
...lear, then seek the appropriate sequence to the begin:
s.clear();
s.seekp(0); // for outputs: seek put ptr to start
s.seekg(0); // for inputs: seek get ptr to start
That will prevent some reallocations done by str by overwriting whatever is in the output buffer currently instead. Results are like...
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...
What's the point of g++ -Wreorder?
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260
Consider:
struct A {
int i;
int j;
A() : j(0), i(j) { }
};
Now i is initialized t...