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Pass a data.frame column name to a function
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Is there any way to pass the column name not as a string?
– kmm
Apr 14 '10 at 23:13
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Convert list to array in Java [duplicate]
...llection to an array: either using
a pre-sized array (like c.toArray(new String[c.size()])) or
using an empty array (like c.toArray(new String[0]). In
older Java versions using pre-sized array was recommended, as the
reflection call which is necessary to create an array of proper size
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Find the host name and port using PSQL commands
I have PSQL running, and am trying to get a perl application connecting to the database. Is there a command to find the current port and host that the database is running on?
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How do you query for “is not null” in Mongo?
...roposition:
db.collection_name.find({"field_name":{$type:2}}) //type:2 == String
You can check on the required attribute's type, it will return all the documents that its field_name queried contains a value because you are checking on the filed's type else if it is null the type condition doesn't...
How do I work around JavaScript's parseInt octal behavior?
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@Grodriguez, and when 0 in |0 is a string?
– Oleg V. Volkov
Oct 24 '14 at 16:29
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Can a class member function template be virtual?
...using MinGW G++ 3.4.5 on Window 7:
#include <iostream>
#include <string>
using namespace std;
template <typename T>
class A{
public:
virtual void func1(const T& p)
{
cout<<"A:"<<p<<endl;
}
};
template <typename T>
class B
: public...
PowerShell script to return versions of .NET Framework on a machine?
...le by looking for unique lines that start with ".NET Framework"
Select-String "^.NET" | Select-Object -Unique |
# And flip it so it's key = value
# And convert ".NET FRAMEWORK 4.5.2" to [version]4.5.2
ForEach-Object {
[version]$v, [int]$k = $_ -replace "\.NET Framework " -s...
Shorten string without cutting words in JavaScript
I'm not very good with string manipulation in JavaScript, and I was wondering how you would go about shortening a string without cutting any word off. I know how to use substring, but not indexOf or anything really well.
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How to check if a particular service is running on Ubuntu
...ed Hat Linux you can see all running services by running the following command:
service --status-all
On the list the + indicates the service is running, - indicates service is not running, ? indicates the service state cannot be determined.
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Difference between 'struct' and 'typedef struct' in C++?
...hat C++
generates a typedef for every tag
name, such as
typedef class string string;
Unfortunately, this is not entirely
accurate. I wish it were that simple,
but it's not. C++ can't generate such
typedefs for structs, unions, or enums
without introducing incompatibilities
with ...