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How to sum a variable by group
... Is there anyway of maintaining an ID column? Say the categories are ordered and the ID column is 1:nrow(df), is it possible to keep the starting position of each category after aggregating? So the ID column would end up as, for example, 1, 3, 4, 7 after collapsing with aggregate. In my case ...
JUnit vs TestNG [closed]
...c annotated method that it finds will be used, but it may find them in any order. This causes us to write different classes unnecessarily. However TestNG provides clean way to provide different kind of data providers for each and every method. So we can test the same unit of code with valid and inva...
jquery input select all on focus
...oblem:
Here's a little bit of explanation:
First, let's take a look at the order of events when you mouse or tab into a field.
We can log all the relevant events like this:
$("input").on("mousedown focus mouseup click blur keydown keypress keyup change",
function(e) { console.log(e.typ...
Fastest way to check if string contains only digits
... testing (always profile because the results depend on hardware, versions, order, etc.):
static bool isDigitsFr(string s) { if (s == null || s == "") return false; for (int i = 0; i < s.Length; i++) if (s[i] < '0' || s[i] > '9') return false; return true; }
static bool isDigitsFu(string s)...
What are all the user accounts for IIS/ASP.NET and how do they differ?
... and setting up IIS. So here goes....
To cover the identities listed:
IIS_IUSRS:
This is analogous to the old IIS6 IIS_WPG group. It's a built-in group with it's security configured such that any member of this group can act as an application pool identity.
IUSR:
This account is analogous to th...
Is there a way to check if int is legal enum in C#?
...
In order to deal with [Flags] you can also use this solution from C# Cookbook:
First, add a new ALL value to your enum:
[Flags]
enum Language
{
CSharp = 1, VBNET = 2, VB6 = 4,
All = (CSharp | VBNET | VB6)
}
Then, ...
Remove elements from collection while iterating
...ection, which would imply a second iteration work to look for this item in order to remove it.
I think it is worth mentioning that the remove method of the Iterator interface is marked as "optional" in Javadocs, which means that there could be Iterator implementations that throw UnsupportedOperatio...
Practical uses for the “internal” keyword in C#
...e once which described the length to which Windows developers had to go in order to keep "bugwards compatibility" with all the older programs that made use of various internal features and bugs. Repeating this error with .NET is not meaningful.
– KT.
Aug 18 '16...
Using --no-rdoc and --no-ri with bundler
...
Order doesn't matter, btw. It's a list of command line flags to pass to gem.
– docwhat
Feb 11 '12 at 20:46
...
How to get pixel data from a UIImage (Cocoa Touch) or CGImage (Core Graphics)?
...orSpace,
kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
CGColorSpaceRelease(colorSpace);
CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);
CGContextRelease(context);
// Now your rawData contains the image data in the RGBA8888 pi...