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What is cardinality in MySQL?
What is cardinality in MySQL? Please explain in simple, non-technical language.
8 Answers
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Android: Test Push Notification online (Google Cloud Messaging) [closed]
...firewall restrictions I can not deploy a test sever for push notification. What I am looking for is a online server which would send some test notifications to my device to test my client implementation.
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What's the best way to use R scripts on the command line (terminal)?
...her than a system-wide/default Rscript (which may not be installed in /usr/whatever). I would recommend using env for R and Rscript stuff, since these in particular may not be installed in standard places. (Ordinary bash scripts however can typically safely always use #!/bin/bash.)
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Dynamically select data frame columns using $ and a character value
... a symbol that needs to be matched, not evaluated.
*/
Second argument? What?! You have to realise that $, like everything else in R, (including for instance ( , + , ^ etc) is a function, that takes arguments and is evaluated. df$V1 could be rewritten as
`$`(df , V1)
or indeed
`$`(df , "V1")
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How do I use raw_input in Python 3
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Starting with Python 3, raw_input() was renamed to input().
From What’s New In Python 3.0, Builtins section second item.
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How to remove the default link color of the html hyperlink 'a' tag?
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… will cause the element to take on the colour of its parent (which is what I think you are looking for).
A live demo follows:
a {
color: inherit;
}
<p>The default color of the html element is black. The default colour of the body and of a paragraph is inherited. This
<a href="...
Where's my JSON data in my incoming Django request?
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Please explain what you mean by 'test client'? What are you trying to do?
– Jared Knipp
Oct 25 '11 at 19:00
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For each row in an R dataframe
... Be careful, as the dataframe is converted to a matrix, and what you end up with (x) is a vector. This is why the above example has to use numeric indexes; the by() approach gives you a data.frame, which makes your code more robust.
– Darren Cook
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What is context in _.each(list, iterator, [context])?
I am new to underscore.js. What is the purpose of [context] in _.each() ? How should it be used?
5 Answers
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How to verify an XPath expression in Chrome Developers tool or Firefox's Firebug?
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@user1177636: What software did you use for generating these GIFs?
– JacekM
Mar 22 '14 at 23:59
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