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Using Linq to get the last N elements of a collection?
...c IEnumerable<T> TakeLast<T>(this IEnumerable<T> source, int N)
{
return source.Skip(Math.Max(0, source.Count() - N));
}
}
A brief note on performance:
Because the call to Count() can cause enumeration of certain data structures, this approach has the risk of cau...
Adding a new SQL column with a default value
...
Try this:
ALTER TABLE table1 ADD COLUMN foo INT DEFAULT 0;
From the documentation that you linked to:
ALTER [ONLINE | OFFLINE] [IGNORE] TABLE tbl_name
alter_specification [, alter_specification] ...
alter_specification:
...
ADD [COLUMN] (col_name colum...
How to check that an object is empty in PHP?
... all
}
If SimpleXMLElement is more than one level deep, you can start by converting it to a pure array:
$obj = simplexml_load_file($url);
// `json_decode(json_encode($obj), TRUE)` can be slow because
// you're converting to and from a JSON string.
// I don't know another simple way to do a deep c...
Picking a random element from a set
How do I pick a random element from a set?
I'm particularly interested in picking a random element from a
HashSet or a LinkedHashSet, in Java.
Solutions for other languages are also welcome.
...
How can I format a decimal to always show 2 decimal places?
...left of the decimal point and two to the right of it and no more...), then converting them to strings with str will work fine:
str(Decimal('10'))
# -> '10'
str(Decimal('10.00'))
# -> '10.00'
str(Decimal('10.000'))
# -> '10.000'
...
How do I remove an item from a stl vector with a certain value?
...e extra elements that are now at the end of the container:
std::vector<int> vec;
// .. put in some values ..
int int_to_remove = n;
vec.erase(std::remove(vec.begin(), vec.end(), int_to_remove), vec.end());
share
...
What is the simplest and most robust way to get the user's current location on Android?
...d(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
};
LocationListener locationListenerNetwork = new LocationListener() {
public void onLocationChanged(Location location) {
timer1.cancel();
locationResult....
C# 'is' operator performance
...ed to test the type of an object to see whether it inherits from a certain interface.
8 Answers
...
Website screenshots
...S, which renders the page and outputs it in a ps file (ghostscript), then, convert it in a .jpg, .png, .pdf.. can be little slower with complex pages (and don't support all the CSS).
Else, you can use wkhtmltopdf to output a html page in pdf, jpg, whatever..
Accept CSS2.0, use the webkit (safari's ...
Kill child process when parent process is killed
...out(LayoutKind.Sequential)]
public struct SECURITY_ATTRIBUTES
{
public int nLength;
public IntPtr lpSecurityDescriptor;
public int bInheritHandle;
}
[StructLayout(LayoutKind.Sequential)]
struct JOBOBJECT_BASIC_LIMIT_INFORMATION
{
public Int64 PerProcessUserTimeLimit;
public Int6...