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Crontab Day of the Week syntax
...e of days, such as MON, THU, etc:
0 - Sun Sunday
1 - Mon Monday
2 - Tue Tuesday
3 - Wed Wednesday
4 - Thu Thursday
5 - Fri Friday
6 - Sat Saturday
7 - Sun Sunday
Graphically:
┌────────── minute (0 - 59)
│ ┌───────...
How to count the number of true elements in a NumPy bool array
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265
You have multiple options. Two options are the following.
numpy.sum(boolarr)
numpy.count_nonz...
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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Maven check for updated dependencies in repository
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287
The Maven Versions plugin and its display-dependency-updates mojo are what you're looking for:...
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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Transform DateTime into simple Date in Ruby on Rails
...ew.to_date
NoMethodError: undefined method 'to_date' for #<DateTime: -1/2,0,2299161>
from (irb):1
>> require 'active_support/core_ext'
=> true
>> DateTime.new.to_date
=> Mon, 01 Jan -4712
share...
Tell Ruby Program to Wait some amount of time
...following convenience syntax:
sleep(4.minutes)
# or, even longer...
sleep(2.hours); sleep(3.days) # etc., etc.
# or shorter
sleep(0.5) # half a second
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improve this answer
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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...
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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List comprehension rebinds names even after scope of comprehension. Is this right?
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172
List comprehensions leak the loop control variable in Python 2 but not in Python 3. Here's Guid...