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Adding a column to a data.frame
...1, 1 + cumsum(nonpos))
> classes
[1] 1 1 1 1 2 2 2 2 2 2 2 3 3 3 3
Now, we can attach it back onto our data frame with cbind (by using the class= syntax, we can give the column the class heading):
> data_w_classes <- cbind(data, class=classes)
And data_w_classes now contains the re...
unable to copy/paste in mingw shell
...ight click the icon on the top left hand corner of MINGW64:
Select Options
Now Select keys
On the right hand you will find Shortcuts
If not thicked, thick Copy and Paste
Now always remeber the instruction given to copy & paste as follows:
Copy: Ctrl+ Ins (insert)
i.e. To copy on MINGW, only h...
Single huge .css file vs. multiple smaller specific .css files? [closed]
... maintain. Highly, highly recommended. I personally use Sass (SCSS syntax) now, but used LESS previously. Both are great, with similar benefits. Once you've written CSS with a compiler, it's unlikely you'd want to do without one.
http://lesscss.org
http://sass-lang.com
If you don't want to mess a...
Rails ActiveRecord date between
...
Day.where(:reference_date => 6.months.ago..Time.now) works, thanks
– boulder_ruby
Nov 5 '12 at 1:41
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What would cause an algorithm to have O(log n) complexity?
My knowledge of big-O is limited, and when log terms show up in the equation it throws me off even more.
6 Answers
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Bomb dropping algorithm
...e to prove we can be greedy in reducing the outer
perimeter.
But, we do know we can be greedy. Because no bomb in layer 2 can ever be more
efficient in reducing layer 2 to 0 than a strategically placed bomb in layer 3. And
for the same reason as before - there is always a bomb we can place in ...
What algorithm gives suggestions in a spell checker?
...n distance is not exactly the right edit distance for a spell checker. It knows only insertion, deletion and substitution. Transposition is missing and produces 2 for a transposition of 1 character (it's 1 delete and 1 insertion). Damerau–Levenshtein distance is the right edit distance.
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Rails Observer Alternatives for 4.0
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They are in a plugin now.
Can I also recommend an alternative which will give you controllers like:
class PostsController < ApplicationController
def create
@post = Post.new(params[:post])
@post.subscribe(PusherListener.new)
@...
Decimal precision and scale in EF Code First
I'm experimenting with this code-first approach, but I'm find out now that a property of type System.Decimal gets mapped to a sql column of type decimal(18, 0).
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A proper wrapper for console.log with correct line number?
I'm now developing an application, and place a global isDebug switch. I would like to wrap console.log for more convenient usage.
...