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Filtering collections in C#
I am looking for a very fast way to filter down a collection in C#. I am currently using generic List collections, but am open to using other structures if they perform better.
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Compare two dates with JavaScript
...you want - construct one for each date, then compare them using the >, <, <= or >=.
The ==, !=, ===, and !== operators require you to use date.getTime() as in
var d1 = new Date();
var d2 = new Date(d1);
var same = d1.getTime() === d2.getTime();
var notSame = d1.getTime() !== d2.getTi...
How to vertically align a html radio button to it's label?
...plain why this is the only correct answer: Some elements in HTML have default margin or padding values, like the <p> or <li> elements or radio buttons. You can see this if you go into developer mode (F12) and hover your mouse over the tag. Actually, this is a good behaviour, because the ...
What is the difference between synchronous and asynchronous programming (in node.js)
...ile system operations, while the main Node thread keeps executing your javascript code. In an event-driven server like Node, the file system thread notifies the main Node thread of certain events such as completion, failure, or progress, along with any data associated with that event (such as the re...
How do I raise a Response Forbidden in django
...rol the rendering of 403 HTTP errors.
As correctly pointed out by @dave-halter, The 403 template can only be used if you raise PermissionDenied
Below is a sample view used to test custom templates "403.html", "404.html" and "500.html"; please make sure to set DEBUG=False in project's settings or t...
How do I get the first element from an IEnumerable in .net?
I often want to grab the first element of an IEnumerable<T> in .net, and I haven't found a nice way to do it. The best I've come up with is:
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Tools for making latex tables in R [closed]
... or \input into your LaTeX. Something like:
\begin{tabular}{l l}
A & <%= fit$A %> \\
B & <%= fit$B %> \\
\end{tabular}
The brew syntax can also handle loops, so you can create a table row for each row of a dataframe.
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Fit cell width to content
... the width of the content within it rather than stretch (which is the default behaviour)?
6 Answers
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Drop unused factor levels in a subsetted data frame
...subsetting:
> subdf$letters
[1] a b c
Levels: a b c d e
subdf$letters <- factor(subdf$letters)
> subdf$letters
[1] a b c
Levels: a b c
EDIT
From the factor page example:
factor(ff) # drops the levels that do not occur
For dropping levels from all factor columns in a dataframe, y...
C++ unordered_map using a custom class type as the key
...rloading operator==() for your key type (as you did already).
The difficulty with the hash function is that if your key type consists of several members, you will usually have the hash function calculate hash values for the individual members, and then somehow combine them into one hash value for ...