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How to check that an object is empty in PHP?
...g doesn't work for me, because I get the error: PHP Parse error: syntax error, unexpected '(array)' (array) (T_ARRAY_CAST) in ... I use PHP version 5.4.28 and the first option with two lines of code works for me.
– Coanda
May 18 '14 at 13:34
...
Does pandas iterrows have performance issues?
...ernally by pandas, though it depends on what is going on inside the apply expression. For example, df.apply(lambda x: np.sum(x)) will be executed pretty swiftly, though of course, df.sum(1) is even better. However something like df.apply(lambda x: x['b'] + 1) will be executed in Python space, and co...
What does “not run” mean in R help pages?
...
"not run" encloses code that shouldn't be executed in the example function (e.g. time-consuming code parts, user-interaction, ...).
see e.g. ?example:
As detailed in the manual Writing R Extensions, the author of
the help page can markup parts of the examples for tw...
What's the reason I can't create generic array types in Java?
... But what about erasure? Why doesn't that apply?
– Qix - MONICA WAS MISTREATED
Mar 5 '13 at 8:22
15
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How to model type-safe enum types?
...
http://www.scala-lang.org/docu/files/api/scala/Enumeration.html
Example use
object Main extends App {
object WeekDay extends Enumeration {
type WeekDay = Value
val Mon, Tue, Wed, Thu, Fri, Sat, Sun = Value
}
import WeekDay._
def isWorkingDay(d: WeekDay) = !...
Why main does not return 0 here?
...r than just a move and a return—so it’s almost certainly a register, eax specifically on x86.
– Jon Purdy
Dec 30 '11 at 9:37
8
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Getting attributes of Enum's value
... to get attributes of the enum values and not of the enum itself? For example, suppose I have the following enum :
24 ...
Difference between “or” and || in Ruby? [duplicate]
...
Here's a ruby operator precedence table.
See this question for another example using and/&&.
Also, be aware of some nasty things that could happen:
a = false || true #=> true
a #=> true
a = false or true #=> true
a #=> false
Both of the previous two statements evalua...
TINYTEXT, TEXT, MEDIUMTEXT, and LONGTEXT maximum storage sizes
Per the MySQL docs , there are four TEXT types:
4 Answers
4
...
How to change identity column values programmatically?
...following structure
CREATE TABLE Test
(
ID INT IDENTITY(1,1) PRIMARY KEY,
X VARCHAR(10)
)
INSERT INTO Test
OUTPUT INSERTED.*
SELECT 'Foo' UNION ALL
SELECT 'Bar' UNION ALL
SELECT 'Baz'
Then you can do
/*Define table with same structure but no IDENTITY*/
CREATE TABLE Temp
(
ID INT PRIMARY KEY,
X...