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R - Concatenate two dataframes?
...olumn b to data frame b.
Results
> a <- data.frame(a=c(0,1,2), b=c(3,4,5), c=c(6,7,8))
> a
a b c
1 0 3 6
2 1 4 7
3 2 5 8
> b <- data.frame(a=c(9,10,11), c=c(12,13,14))
> b
a c
1 9 12
2 10 13
3 11 14
> b$b <- NA
> b
a c b
1 9 12 NA
2 10 13 NA
3 11 14 NA
> ...
What is a non-capturing group in regular expressions?
...ow.com/"
Group 1: "http"
Group 2: "stackoverflow.com"
Group 3: "/"
Match "https://stackoverflow.com/questions/tagged/regex"
Group 1: "https"
Group 2: "stackoverflow.com"
Group 3: "/questions/tagged/regex"
But I don't care about the protocol -- I just want the host an...
In Python, how do I iterate over a dictionary in sorted key order?
...
173
Haven't tested this very extensively, but works in Python 2.5.2.
>>> d = {"x":2, "h":1...
Why do I need 'b' to encode a string with Base64?
...mail.
Hence, it wants a string of 8-bit bytes. You create those in Python 3 with the b'' syntax.
If you remove the b, it becomes a string. A string is a sequence of Unicode characters. base64 has no idea what to do with Unicode data, it's not 8-bit. It's not really any bits, in fact. :-)
In your ...
Passing data to a bootstrap modal
...lt;button class="close" data-dismiss="modal">×</button>
<h3>Modal header</h3>
</div>
<div class="modal-body">
<p>some content</p>
<input type="text" name="bookId" id="bookId" value=""/>
</div>
</div>
JAVA...
Python: List vs Dict for look up table
...M. Kuchling in Beautiful Code, the implementation tries to keep the hash 2/3 full, so you might waste quite some memory.
If you do not add new entries on the fly (which you do, based on your updated question), it might be worthwhile to sort the list and use binary search. This is O(log n), and is ...
How to edit one specific row in Microsoft SQL Server Management Studio 2008?
...
3 Answers
3
Active
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How to measure elapsed time in Python?
...
35 Answers
35
Active
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How to declare std::unique_ptr and what is the use of it?
...accepts a T*).
In the first example:
unique_ptr<int> uptr (new int(3));
The pointer is the result of a new expression, while in the second example:
unique_ptr<double> uptr2 (pd);
The pointer is stored in the pd variable.
Conceptually, nothing changes (you are constructing a uniqu...
How to install 2 Anacondas (Python 2 and 3) on Mac OS
...ust installed XCode (for c++ compiler) and Anaconda with the latest Python 3 (for myself). Now I'm wondering how to install properly second Anaconda (for work) with Python 2?
...