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how do you filter pandas dataframes by multiple columns
...sub-statements with ():
males = df[(df[Gender]=='Male') & (df[Year]==2014)]
To store your dataframes in a dict using a for loop:
from collections import defaultdict
dic={}
for g in ['male', 'female']:
dic[g]=defaultdict(dict)
for y in [2013, 2014]:
dic[g][y]=df[(df[Gender]==g) & ...
Rails migrations: Undo default setting for a column
...shua Pinter
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answered Nov 17 '09 at 2:36
Jeremy MackJeremy Mack
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How to change checkbox's border style in CSS?
...I change checkbox (input) border's style? I've put border:1px solid #1e5180 upon it, but in FireFox 3.5, nothing happens!
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PostgreSQL, checking date relative to “today”
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answered Oct 13 '10 at 22:37
Paul TomblinPaul Tomblin
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Replacement for “rename” in dplyr
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dplyr version 0.3 added a new rename() function that works just like plyr::rename().
df <- rename(df, new_name = old_name)
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What does flushing the buffer mean?
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David HeffernanDavid Heffernan
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CSS div element - how to show horizontal scroll bars only?
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How to change the default font size in ggplot2
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Use theme_set()
theme_set(theme_gray(base_size = 18))
qplot(1:10, 1:10)
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How to remove array element in mongodb?
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answered Jun 6 '13 at 10:25
Leonid BeschastnyLeonid Beschastny
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How to map and remove nil values in Ruby
...ct it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simply:
items.filter_map { |x| process_x url }
"Ruby 2.7 adds Enumerable#filter_map" is a good read on t...