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Group by multiple columns in dplyr, using string vector input
...e so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data %...
Create Pandas DataFrame from a string
...
538
A simple way to do this is to use StringIO.StringIO (python2) or io.StringIO (python3) and pass...
What's the difference between `raw_input()` and `input()` in Python 3?
What is the difference between raw_input() and input() in Python 3?
6 Answers
6
...
Looping through a hash, or using an array in PowerShell
... property. Here is an example how:
$hash = @{
a = 1
b = 2
c = 3
}
$hash.Keys | % { "key = $_ , value = " + $hash.Item($_) }
Output:
key = c , value = 3
key = a , value = 1
key = b , value = 2
share
...
Reactjs: Unexpected token '
...
Yuliia AshomokYuliia Ashomok
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...
How to perform element-wise multiplication of two lists?
...gahooagahooa
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9
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TypeError: module.__init__() takes at most 2 arguments (3 given)
...
answered Jan 29 '13 at 14:07
SheenaSheena
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What's valid and what's not in a URI query?
...aracter must be within data.
The current standard for generic URIs is RFC 3986, which has this to say:
2.2. Reserved Characters
URIs include components and subcomponents that are delimited by characters in the "reserved" set. These characters are called "reserved" because they may (or may not) be...
Unique (non-repeating) random numbers in O(1)?
... = n, max starts off at 10:
+--+--+--+--+--+--+--+--+--+--+--+
| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9|10|
+--+--+--+--+--+--+--+--+--+--+--+
^
max
At each iteration, a random number r is selected between 0 and max, array[r] and array[max]...