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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"...
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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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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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...
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.
...
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...
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...
How to split a string literal across multiple lines in C / Objective-C?
...ocumenting the optionality of the second @?
– Heath Borders
Jun 5 '12 at 18:10
@HeathBorders: Not right here, but I've...
How to elegantly check if a number is within a range?
...
As others said, use a simple if.
You should think about the ordering.
e.g
1 <= x && x <= 100
is easier to read than
x >= 1 && x <= 100
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How to select the rows with maximum values in each group with dplyr? [duplicate]
...g of A and B values.
group_by( A, B) %>%
# Sort rows in descending order by "value" column.
arrange( desc(value) ) %>%
# Pick the top 1 value
slice(1) %>%
# Remember to ungroup in case you want to do further work without grouping.
ungroup()
# Answering an extension of the ...