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List comprehension: Returning two (or more) items for each item
Is it possible to return 2 (or more) items for each item in a list comprehension?
6 Answers
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Cartesian product of multiple arrays in JavaScript
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2020 Update: 1-line (!) answer with vanilla JS
Original 2017 Answer: 2-line answer with vanilla JS:
(see updates below)
All of the answers here are overly complicated, most of them take 20 lines of code or even more.
This exa...
Remove empty elements from an array in Javascript
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Determine device (iPhone, iPod Touch) with iOS
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Why does the order of the loops affect performance when iterating over a 2D array?
...y location in the array: x[i][j]. Here's a bit of insight why:
You have a 2-dimensional array, but memory in the computer is inherently 1-dimensional. So while you imagine your array like this:
0,0 | 0,1 | 0,2 | 0,3
----+-----+-----+----
1,0 | 1,1 | 1,2 | 1,3
----+-----+-----+----
2,0 | 2,1 | 2,2 ...
How can I exclude all “permission denied” messages from “find”?
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Note:
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Find the max of two or more columns with pandas
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2 Answers
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Active
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How to deal with SettingWithCopyWarning in Pandas?
...copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] = new_val
However, this doesn't fit your usage, which is equivalent to:
df = df[df['A'] > ...
How can I debug git/git-shell related problems?
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For even more verbose output use following:
GIT_CURL_VERBOSE=1 GIT_TRACE=1 git pull origin ma...
Can dplyr package be used for conditional mutating?
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Use ifelse
df %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
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