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How to Correctly Use Lists in R?
...st?) contemporary programming languages in widespread use have at least a handful of ADTs [abstract data types] in common, in particular,
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Bad value X-UA-Compatible for attribute http-equiv on element meta
I have used the same meta that HTML5 Boilerplate is using, and the W3C HTML validator complains:
8 Answers
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Rotating and spacing axis labels in ggplot2
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In the newest version of ggplot2 the command would be: q + theme(axis.text.x=element_text(angle = -90, hjust = 0))
– rnorberg
Sep 28 '12 at 13:18
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How to append rows to an R data frame
...rs 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 fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n)...
Fast check for NaN in NumPy
... to get slower as NaNs get closer to the start of the array. On the other hand, sum's throughput seems constant regardless of whether there are NaNs and where they're located:
In [40]: x = np.random.rand(100000)
In [41]: %timeit np.isnan(np.min(x))
10000 loops, best of 3: 153 us per loop
In [42]:...
How to sort mongodb with pymongo
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.sort(), in pymongo, takes key and direction as parameters.
So if you want to sort by, let's say, id then you should .sort("_id", 1)
For multiple fields:
.sort([("field1", pymongo.ASCENDING), ("field2", pymongo.DESCENDING)])
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How do I apply a CSS class to Html.ActionLink in ASP.NET MVC?
I'm building an ASP.NET MVC application, using VB.NET and I'm trying to apply a css class to a Html.ActionLink using the code:
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What is the best regular expression to check if a string is a valid URL?
...$IRI . '|' . $irelative_ref);
Edit 7 March 2011: Because of the way PHP handles backslashes in quoted strings, these are unusable by default. You'll need to double-escape backslashes except where the backslash has a special meaning in regex. You can do that this way:
$escape_backslash = '/(?<!...
How to count the number of set bits in a 32-bit integer?
...ays addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's popcnt, on CPUs where it's supported)...
Library? Static? Dynamic? Or Framework? Project inside another project
I have an existing iOS app and want to add a large chunk of code that I've been developing as another project just for ease of testing. The new chunk basically deals with saving an image to various sharing services, etc.. Because that sharing code needs a lot of testing and future updating, I was wo...