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Applying a function to every row of a table using dplyr?
... the intersection of purrr and dplyr. They have been removed from purrr in order to make the package lighter and because they have been replaced by other solutions in the tidyverse.
So, you will need to install + load that package to make the code below work.
Original post
Hadley frequently chan...
SQL Case Sensitive String Compare
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List comprehension: Returning two (or more) items for each item
...I used to find them a little confusing because I kept trying to invert the order.
– DSM
Aug 8 '12 at 17:07
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How do I print out the contents of an object in Rails for easy debugging?
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I generally first try .inspect, if that doesn't give me what I want, I'll switch to .to_yaml.
class User
attr_accessor :name, :age
end
user = User.new
user.name = "John Smith"
user.age = 30
puts user.inspect
#=> #<User:0x...
How to see which commits in one branch aren't in the other?
...bout
git log next..devel
Result is similar to Byran's answer (different order of commits) but both of our answers will produce commits that are different between the branches, rather just showing what's in one branch and not in the other.
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Join/Where with LINQ and Lambda
... the syntax relationships, but I put this document together for my team in order to make it a little simpler for them to understand. Hope this helps someone
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Scala: Abstract types vs generics
...ed type abstraction
abstract class MaxCell extends AbsCell {
type T <: Ordered { type O = T }
def setMax(x: T) = if (get < x) set(x)
}
Here, the type declaration of T is constrained by an upper type bound which consists of a class name Ordered and a refinement { type O = T }.
The upper...
ActionBarCompat: java.lang.IllegalStateException: You need to use a Theme.AppCompat
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Excellent, I missed this. Don't forget all the other -vXX folders as well, or it'll work fine in your test env, only to bite you once someone uses one of those versions.
– falstro
Jan 20 '14 at 11:27
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append new row to old csv file python
...e to append a new row opening the file in 'a'mode.
Even in windows, in order to avoid the newline problem, you must declare it as newline=''.
Now you can open the file in 'a'mode (without the b).
import csv
with open(r'names.csv', 'a', newline='') as csvfile:
fieldnames = ['This','aN...
Difference between addSubview and insertSubview in UIView class
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Using insertSubView: you can specify the index, which determines z-order of views. A view with a higher index lies above those with lower indices.
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