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Scraping html tables into R data frames using the XML package
...t(lapply(tables, function(t) dim(t)[1]))
the picked table is the longest one on the page
tables[[which.max(n.rows)]]
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Makefile variable as prerequisite
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I know that this is an ancient reply, but perhaps someone is still watching it otherwise I might re-post this as a new question... I am trying to implement this implicit target "guard" to check for set environment variables and it works in principle, however the commands in the ...
How to append rows to an R data frame
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Update
Not knowing what you are trying to do, I'll share one more suggestion: Preallocate vectors of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fa...
What is the difference between Unidirectional and Bidirectional JPA and Hibernate associations?
...ctions.
Note that navigational access is not always good, especially for "one-to-very-many" and "many-to-very-many" relationships. Imagine a Group that contains thousands of Users:
How would you access them? With so many Users, you usually need to apply some filtering and/or pagination, so that y...
C++: Rounding up to the nearest multiple of a number
OK - I'm almost embarrassed posting this here (and I will delete if anyone votes to close) as it seems like a basic question.
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Using @property versus getters and setters
...ey are syntactically identical to attribute access, so you can change from one to another without any changes to client code. You could even have one version of a class that uses properties (say, for code-by-contract or debugging) and one that doesn't for production, without changing the code that u...
Is there a link to the “latest” jQuery library on Google APIs? [duplicate]
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Linking to the google API one is likely to increase your website speed due to the fact that there is a high chance your user already has it cached from another website, and therefore will not need to download it again from you. Hosting it yourself jus...
Email address validation using ASP.NET MVC data type attributes
...e solution is to use EmailAddressAttribute which resides inside System.ComponentModel.DataAnnotations.
Your code should look similar to this:
[Display(Name = "Email address")]
[Required(ErrorMessage = "The email address is required")]
[EmailAddress(ErrorMessage = "Invalid Email Address")]
public s...
Hidden features of Scala
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Okay, I had to add one more. Every Regex object in Scala has an extractor (see answer from oxbox_lakes above) that gives you access to the match groups. So you can do something like:
// Regex to split a date in the format Y/M/D.
val regex = ...
Can I use a hash sign (#) for commenting in PHP?
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I much prefer # comments over // ones .. but I've always been wondering if # is PSR complient .. Is it ?
– Stphane
Aug 11 '15 at 7:36
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