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python dataframe pandas drop column using int
I understand that to drop a column you use df.drop('column name', axis=1). Is there a way to drop a column using a numerical index instead of the column name?
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Pythonic way to print list items
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Assuming you are using Python 3.x:
print(*myList, sep='\n')
You can get the same behavior on Python 2.x using from __future__ import print_function, as noted by mgilson in comments.
With the print statement on Python 2.x you will need iteration of some ...
Entity Framework - Invalid Column Name '*_ID"
... issue between Code First and Database first EF, but I'm not sure how to fix it. I'll try to be as clear as I can, but I honestly am missing some of the understanding here myself. This is Entity Framework 4.4
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The smallest difference between 2 Angles
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A more concise, though potentially more expensive, equivalent of the latter approach's second statement, is a -= 360*sgn(a)*(abs(a) > 180). (Come to think of it, if you've branchless implementations of sgn and abs, then that characteristic might actually start to...
Label encoding across multiple columns in scikit-learn
...r ago, and generated many upvotes (including a bounty), I should probably extend this further.
For inverse_transform and transform, you have to do a little bit of hack.
from collections import defaultdict
d = defaultdict(LabelEncoder)
With this, you now retain all columns LabelEncoder as diction...
Why is super.super.method(); not allowed in Java?
...our (particularly from within the same method) but not your parent's. For example, suppose we have a base "collection of items", a subclass representing "a collection of red items" and a subclass of that representing "a collection of big red items". It makes sense to have:
public class Items
{
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How to sort an array in descending order in Ruby
...{
ary << {:bar => rand(1000)}
}
n = 500
Benchmark.bm(20) do |x|
x.report("sort") { n.times { ary.sort{ |a,b| b[:bar] <=> a[:bar] } } }
x.report("sort reverse") { n.times { ary.sort{ |a,b| a[:bar] <=> b[:bar] }.reverse } }
x.report("sort_by -a[:bar]...
Iterating over dictionaries using 'for' loops
... To loop over both key and value you can use the following:
For Python 3.x:
for key, value in d.items():
For Python 2.x:
for key, value in d.iteritems():
To test for yourself, change the word key to poop.
In Python 3.x, iteritems() was replaced with simply items(), which returns a set-like ...
What are the rules for the “…” token in the context of variadic templates?
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In the context of variadic template, the ellipsis ... is used to unpack the template parameter pack if it appears on the right side of an expression (call this expression pattern for a moment), or it's a pack argument if it appears on le...
Paging UICollectionView by cells, not screen
...h;
int minSpace = 10;
int cellToSwipe = (scrollView.contentOffset.x)/(pageWidth + minSpace) + 0.5; // cell width + min spacing for lines
if (cellToSwipe < 0) {
cellToSwipe = 0;
} else if (cellToSwipe >= self.articles.count) {
cellToSwipe = self.articles.count -...