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How to convert a set to a list in python?
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197
It is already a list
type(my_set)
>>> <type 'list'>
Do you want something li...
How exactly does tail recursion work?
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169
The compiler is simply able to transform this
int fac_times (int n, int acc) {
if (n == 0...
numpy: most efficient frequency counts for unique values in an array
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16 Answers
16
Active
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How to set versionName in APK filename using gradle?
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14 Answers
14
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Determine the data types of a data frame's columns
...se ?str(). To explore some examples, let's make some data:
set.seed(3221) # this makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
@...
Rotating a two-dimensional array in Python
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Consider the following two-dimensional list:
original = [[1, 2],
[3, 4]]
Lets break it down step by step:
>>> original[::-1] # elements of original are reversed
[[3, 4], [1, 2]]
This list is passed into zip() using argument unpacking, so the zip call ends...
Installing specific package versions with pip
I'm trying to install version 1.2.2 of the MySQL_python adaptor, using a fresh virtualenv created with the --no-site-packages option. The current version shown in PyPi is 1.2.3 . Is there a way to install the older version? I found an article stating that this should do it:
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how do I insert a column at a specific column index in pandas?
... the beginning
df.insert(loc, column, value)
df = pd.DataFrame({'B': [1, 2, 3], 'C': [4, 5, 6]})
df
Out:
B C
0 1 4
1 2 5
2 3 6
idx = 0
new_col = [7, 8, 9] # can be a list, a Series, an array or a scalar
df.insert(loc=idx, column='A', value=new_col)
df
Out:
A B C
0 7 1 ...