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Split a vector into chunks in R
... f)
if(force.number.of.groups) {
g.names <- names(g)
g.names.ordered <- as.character(sort(as.numeric(g.names)))
} else {
g.names <- names(g[-length(g)])
g.names.ordered <- as.character(sort(as.numeric(g.names)))
g.names.ordered <- c(g.names.ordered, "overflow"...
To ARC or not to ARC? What are the pros and cons? [closed]
...n't become a decent intermediate programmer. You need to know the rules in order to bridge correctly with Core Foundation, and every intermediate programmer needs to deal with CF at some point. And you need to know the rules for mixed-ARC/MRC code. And you need to know the rules when you start messi...
What are the use cases for selecting CHAR over VARCHAR in SQL?
...omerNumber on a demographic table, or CodeID on a decode table, or perhaps OrderNumber on an order table. By using char, the query engine can more quickly perform the join because it can do straight pointer arithmetic (deterministically) rather than having to move it's pointers a variable amount of...
Is Using .NET 4.0 Tuples in my C# Code a Poor Design Decision?
...group of types that share a similar structure, and treating them simply as ordered set of values. In all cases, a benefit of tuples is that they avoid cluttering your namespace with data-only classes that expose properties but not methods.
Here's an example of a reasonable use for Tuple<>:
v...
How to Select Columns in Editors (Atom,Notepad++, Kate, VIM, Sublime, Textpad,etc) and IDEs (NetBean
How to select columns in Editors and IDEs to columnar delete, insert or replace some characters ?
21 Answers
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Can a foreign key be NULL and/or duplicate?
...from a FK without adding a further constraint on the field. So you have an order table and the order details table for instance. If the customer orders ten items at one time, he has one order and ten order detail records that contain the same orderID as the FK.
...
How to make a query with group_concat in sql server [duplicate]
...AX)'), 1, 1, '')
FROM dbo.tblmask m
JOIN dbo.school s ON s.ID = m.schoolid
ORDER BY m.maskname
Additional information:
String Aggregation in the World of SQL Server
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When should I use a List vs a LinkedList
... curNode = list.First;
for (var k = 0; k < i/2; k++) // In order to insert a node at the middle of the list we need to find it
curNode = curNode.Next;
list.AddAfter(curNode, a); // Insert it after
}
decimal sum = 0;
foreach (var i...
Can anyone explain CreatedAtRoute() to me?
... when you invoke a POST method to store some new object.
So if you POST an order item for instance, you might return a route like 'api/order/11' (11 being the id of the order obviously).
BTW I agree that the MSDN article is of no use in understanding this. The route you actually return will natural...
Separation of business logic and data access in django
...ation e-mail is sent to the user
and an entry is added to the system log
(etc. etc.)
Such scenario's are useful to see how different parts of your infrastructure can be affected by a single command – in this case your database (some kind of 'active' flag), your mail server, your system log, etc...