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Get: TypeError: 'dict_values' object does not support indexing when using python 3.2.3 [duplicate]
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3 Answers
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Why should eval be avoided in Bash, and what should I use instead?
...# Arguments to printf:
# 1 -> "$1\n"
# 2 -> "$2"
# 3 -> "$3"
# 4 -> "$4"
# etc.
printf "$1\n" "${@:2}"
}
function error
{
# Send the first element as one argument, and the rest of the elements as a combined argument.
# Arguments to println:
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get list from pandas dataframe column
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534
Pandas DataFrame columns are Pandas Series when you pull them out, which you can then call x.to...
Why do enum permissions often have 0, 1, 2, 4 values?
...are people always using enum values like 0, 1, 2, 4, 8 and not 0, 1, 2, 3, 4 ?
7 Answers
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Is there a better way to iterate over two lists, getting one element from each list for each iterati
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answered Dec 17 '09 at 2:03
Roberto BonvalletRoberto Bonvallet
25.9k55 gold badges3737 silver badges5555 bronze badges
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Element-wise addition of 2 lists?
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371
Use map with operator.add:
>>> from operator import add
>>> list( map(add, ...
Select multiple columns in data.table by their numeric indices
... all just work:
library(data.table)
dt <- data.table(a = 1, b = 2, c = 3)
# select single column by index
dt[, 2]
# b
# 1: 2
# select multiple columns by index
dt[, 2:3]
# b c
# 1: 2 3
# select single column by name
dt[, "a"]
# a
# 1: 1
# select multiple columns by name
dt[, c("a", ...
How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
I have a dataframe with ~300K rows and ~40 columns.
I want to find out if any rows contain null values - and put these 'null'-rows into a separate dataframe so that I could explore them easily.
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What does the “yield” keyword do?
...ng its items one by one is called iteration:
>>> mylist = [1, 2, 3]
>>> for i in mylist:
... print(i)
1
2
3
mylist is an iterable. When you use a list comprehension, you create a list, and so an iterable:
>>> mylist = [x*x for x in range(3)]
>>> for i in my...
Extract first item of each sublist
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Using list comprehension:
>>> lst = [['a','b','c'], [1,2,3], ['x','y','z']]
>>> lst2 = [item[0] for item in lst]
>>> lst2
['a', 1, 'x']
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