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Are Exceptions in C++ really slow
...ivial to measure:
The side-table is generally cold, and thus fetching it from memory takes a long time
Determining the right handler involves RTTI: many RTTI descriptors to fetch, scattered around memory, and complex operations to run (basically a dynamic_cast test for each handler)
So, mostly c...
How do I sort an observable collection?
... of the sorted partition from the unsorted. Worst case O(n). Essentially a selection sort (See below for output).
public static void Sort<T>(this ObservableCollection<T> collection)
where T : IComparable<T>, IEquatable<T>
{
List<T> sorted = collectio...
Sort a list from another list IDs
...; source,
IEnumerable<TId> order,
Func<T, TId> idSelector)
{
var lookup = source.ToDictionary(idSelector, t => t);
foreach (var id in order)
{
yield return lookup[id];
}
}
Is a generic extension for what you want.
You could use the extension li...
How to handle checkboxes in ASP.NET MVC forms?
...each (var o in ViewData.Model) { %>
<input type="checkbox" name="selectedObjects" value="<%=o.Id%>">
<%= o.Name %>
<%}%>
<input type="submit" value="Submit" />
<%}%>
Your checkboxes are all called selectedObjects, and the value of each checkbox is...
How do you reset the Zoom in Visual Studio 2010 and above
...
There is a select box for this at the bottom left of the editor window - choose 100% ;)
I was unable to find a keyboard shortcut for it, though zooming in and out can be done using Ctrl + > and Ctrl + <.
Please note the horizo...
How can I remove an SSH key?
...gether.
Go to System --> Preferences --> Startup Applications, and unselect the "SSH Key Agent (Gnome Keyring SSH Agent)" box -- you'll need to scroll down to find it.
You'll still get an ssh-agent, only now it will behave sanely: no keys autoloaded, you run ssh-add to add them, and if you w...
Decimal precision and scale in EF Code First
...mp; t.Namespace == "YOURMODELNAMESPACE"
select t)
{
foreach (var propAttr in classType.GetProperties(BindingFlags.Public | BindingFlags.Instance).Where(p => p.GetCustomAttribute<DecimalPrecisionAttribute>() != null).Select(
p ...
Fastest way to extract frames using ffmpeg?
...actly which frames to extract, eg 1, 200, 400, 600, 800, 1000, try using:
select='eq(n\,1)+eq(n\,200)+eq(n\,400)+eq(n\,600)+eq(n\,800)+eq(n\,1000)' \
-vsync vfr -q:v 2
I'm using this with a pipe to Imagemagick's montage to get 10 frames preview from any videos. Obviously the frame numbers ...
Look up all descendants of a class in Ruby
...e:
class Parent
def self.descendants
ObjectSpace.each_object(Class).select { |klass| klass < self }
end
end
class Child < Parent
end
class GrandChild < Child
end
puts Parent.descendants
puts Child.descendants
puts Parent.descendants gives you:
GrandChild
Child
puts Child.de...
What is the Oracle equivalent of SQL Server's IsNull() function?
...
Instead of ISNULL(), use NVL().
T-SQL:
SELECT ISNULL(SomeNullableField, 'If null, this value') FROM SomeTable
PL/SQL:
SELECT NVL(SomeNullableField, 'If null, this value') FROM SomeTable
...