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Summarizing multiple columns with dplyr? [duplicate]
I'm struggling a bit with the dplyr-syntax. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
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handle textview link click in my android app
I'm currently rendering HTML input in a TextView like so:
13 Answers
13
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Is the pImpl idiom really used in practice?
I am reading the book "Exceptional C++" by Herb Sutter, and in that book I have learned about the pImpl idiom. Basically, the idea is to create a structure for the private objects of a class and dynamically allocate them to decrease the compilation time (and also hide the private implementatio...
NSLog with CGPoint data
...first answer is the easiest and lightest weight way. But this gets me both x and y from the CGPoint in one set. Nice :) Great tool :)
– Spanky
Sep 25 '09 at 18:29
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How to center align the cells of a UICollectionView?
... layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
return UIEdgeInsetsMake(0, 100, 0, 0);
}
You will have to play around with that number to figure out how to force the content into a single line. The first 0, is the top edge argument, you could a...
Getting exact error type in from DbValidationException
...q) and paste in there:
((System.Data.Entity.Validation.DbEntityValidationException)ex).EntityValidationErrors
This will allow you to drill down into the ValidationErrors tree. It's the easiest way I've found to get instant insight into these errors.
For Visual 2012+ users who care only about the...
How do I make UITableViewCell's ImageView a fixed size even when the image is smaller
...of images I am using for cell's image views, they are all no bigger than 50x50. e.g. 40x50, 50x32, 20x37 .....
16 Answer...
How to map with index in Ruby?
....8.7 or 1.9, you can use the fact that iterator methods like each_with_index, when called without a block, return an Enumerator object, which you can call Enumerable methods like map on. So you can do:
arr.each_with_index.map { |x,i| [x, i+2] }
In 1.8.6 you can do:
require 'enumerator'
arr.enum_...
What is the difference between supervised learning and unsupervised learning? [closed]
...tween supervised and unsupervised learning?
Can you provide a basic, easy explanation with an example?
29 Answers
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Set cookie and get cookie with JavaScript [duplicate]
...en I choose a file, it should be saved to a cookie for about a week. The next time you open your HTML file, it should be the previous file you've chosen.
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