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Get column index from column name in python pandas
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388
Sure, you can use .get_loc():
In [45]: df = DataFrame({"pear": [1,2,3], "apple": [2,3,4], "ora...
What is the difference between HashSet and List?
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MySQL: Set user variable from result of query
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edited Oct 8 '10 at 8:18
answered Oct 8 '10 at 8:08
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Assign multiple columns using := in data.table, by group
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This now works in v1.8.3 on R-Forge. Thanks for highlighting it!
x <- data.table(a = 1:3, b = 1:6)
f <- function(x) {list("hi", "hello")}
x[ , c("col1", "col2") := f(), by = a][]
# a b col1 col2
# 1: 1 1 hi hello
# 2: 2 2 hi hell...
What is the difference between NaN and None?
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edited Nov 22 '17 at 18:10
JiminyCricket
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What is the difference between shallow copy, deepcopy and normal assignment operation?
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grcgrc
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How to append multiple values to a list in Python
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384
You can use the sequence method list.extend to extend the list by multiple values from any kind...
How to convert floats to human-readable fractions?
...ational approximation to given real number
** David Eppstein / UC Irvine / 8 Aug 1993
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** With corrections from Arno Formella, May 2008
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** usage: a.out r d
** r is real number to approx
** d is the maximum denominator allowed
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** based on the theory of continued fractions
** if x = a1 + 1...
Using multiple arguments for string formatting in Python (e.g., '%s … %s')
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