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Name of this month (Date.today.month as name)
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edited Jan 23 '15 at 23:15
answered Jan 30 '11 at 17:18
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Appending an element to the end of a list in Scala
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List(1,2,3) :+ 4
Results in List[Int] = List(1, 2, 3, 4)
Note that this operation has a complexity of O(n). If you need this operation frequently, or for long lists, consider using another data type (e.g. a ListBuffer).
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How can I create a correlation matrix in R?
I have 92 set of data of same type.
5 Answers
5
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Right way to initialize an OrderedDict using its constructor such that it retains order of initial d
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2 Answers
2
Active
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python pandas: apply a function with arguments to a series
...w documentation). So now you can do:
my_series.apply(your_function, args=(2,3,4), extra_kw=1)
The positional arguments are added after the element of the series.
For older version of pandas:
The documentation explains this clearly. The apply method accepts a python function which should have ...
Regex how to match an optional character
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256
Use
[A-Z]?
to make the letter optional. {1} is redundant. (Of course you could also write [...
How to show SQL queries run in the Rails console?
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254
Rails 3+
Enter this line in the console:
ActiveRecord::Base.logger = Logger.new(STDOUT)
Ra...
Pass a data.frame column name to a function
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You can just use the column name directly:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[,column])
}
fun1(df, "B")
fun1(df, c("B","A"))
There's no need to use substitute, eval, etc.
You can even pass the desired function as a parameter:
fun1 <- function...
Class with Object as a parameter
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In Python2 this declares Table to be a new-style class (as opposed to "classic" class).
In Python3 all classes are new-style classes, so this is no longer necessary.
New style classes have a few special attributes that classic classe...
How to use Bash to create a folder if it doesn't already exist?
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280
First, in bash "[" is just a command, which expects string "]" as a last argument, so the whit...