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Replace all 0 values to NA
...That is, R does not reserve any space for this null object.2 Meanwhile, looking at ?'NA' we see that
NA is a logical constant of length 1 which contains a missing value
indicator. NA can be coerced to any other vector type except raw.
Importantly, NA is of length 1 so that R reserves some sp...
How to install python3 version of package via pip on Ubuntu?
... python2.7 and python3.2 installed in Ubuntu 12.04 .
The symbolic link python links to python2.7 .
17 Answers
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String formatting named parameters?
I know it's a really simple question, but I have no idea how to google it.
6 Answers
6...
Get and Set a Single Cookie with Node.js HTTP Server
I want to be able to set a single cookie, and read that single cookie with each request made to the nodejs server instance. Can it be done in a few lines of code, without the need to pull in a third party lib?
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Razor view engine, how to enter preprocessor(#if debug)
...turn true;
#else
return false;
#endif
}
Then used it in my views like so:
<section id="sidebar">
@Html.Partial("_Connect")
@if (!Html.IsDebug())
{
@Html.Partial("_Ads")
}
<hr />
@RenderSection("Sidebar", required: false)
</section>
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Javascript Equivalent to C# LINQ Select
...
Since array.map isn't supported in older browsers, I suggest that you stick with the jQuery method.
If you prefer the other one for some reason you could always add a polyfill for old browser support.
You can always add custom methods to the array prototype as well:
Array.prototype.select = func...
Does delete on a pointer to a subclass call the base class destructor?
... delete it if it was allocated on the heap. If it was allocated on the stack this happens automatically (i.e. when it goes out of scope; see RAII). If it is a member of a class (not a pointer, but a full member), then this will happen when the containing object is destroyed.
class A
{
char *so...
How do I check in SQLite whether a table exists?
How do I, reliably , check in SQLite, whether a particular user table exists?
22 Answers
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Convert list to array in Java [duplicate]
...list.size()];
list.toArray(array); // fill the array
Note that this works only for arrays of reference types. For arrays of primitive types, use the traditional way:
List<Integer> list = ...;
int[] array = new int[list.size()];
for(int i = 0; i < list.size(); i++) array[i] = list.get(i...
MySQL Great Circle Distance (Haversine formula)
I've got a working PHP script that gets Longitude and Latitude values and then inputs them into a MySQL query. I'd like to make it solely MySQL. Here's my current PHP Code:
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