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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
..., this is one of the best summaries I've seen put together to date: http://www.vertabelo.com/blog/technical-articles/sql-joins
But back to this question - here are the results for the setdiff() code when using the OP's data:
> a1
a b
1 1 a
2 2 b
3 3 c
4 4 d
5 5 e
> a2
a b
1 1 a
2 2 b
3 ...
Meaning of $? (dollar question mark) in shell scripts
...special variables like this, as you can see on this online manual: https://www.gnu.org/s/bash/manual/bash.html#Special-Parameters
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Android YouTube app Play Video Intent
...bIntent = new Intent(Intent.ACTION_VIEW,
Uri.parse("http://www.youtube.com/watch?v=" + id));
try {
context.startActivity(appIntent);
} catch (ActivityNotFoundException ex) {
context.startActivity(webIntent);
}
}
Note: Beware when you are using this met...
Margin while printing html page
...html body element, which is normally controlled by the browser. See http://www.w3.org/TR/1998/REC-CSS2-19980512/page.html.
This currently works in all major browsers except Safari.
In Internet explorer, the margin is actually set to this value in the settings for this printing, and if you do Previe...
send/post xml file using curl command line
...rl to pass the data to the
server using the content-type
application/x-www-form-urlencoded.
Compare to -F/--form.
-d/--data is the same as --data-ascii. To post data purely binary, you should
instead use the --data-binary option.
To URL-encode the value of a form
field you may use -...
Validating with an XML schema in Python
...
The PyXB package at http://pyxb.sourceforge.net/ generates validating bindings for Python from XML schema documents. It handles almost every schema construct and supports multiple namespaces.
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NPM - How to fix “No readme data”
...rue in your package.json, then npm will refuse to publish it. ref: https://www.npmjs.org/doc/files/package.json.html
– AlexStack
Nov 5 '14 at 12:51
3
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HTML if image is not found
...s not found image ( 404.svg ).
<img id="currentPhoto" src="https://www.ccrharrow.org/Images/content/953/741209.pg" onerror="this.src='https://www.unesale.com/ProductImages/Large/notfound.png'" alt="">
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AngularJS : Factory and Service? [duplicate]
...can.blogspot.in/2013/05/angular-service-or-factory.html
http://viralpatel.net/blogs/angularjs-service-factory-tutorial/
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What is the difference between id and class in CSS, and when should I use them? [duplicate]
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@kj7 Have a play jsfiddle.net/PcxQX - you should try not to use classes with conflicting styles though because it doesn't really make sense, right ("This element is both red and blue." or "This element is both bold and non-bold.")?
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