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Sample random rows in dataframe
...
First make some data:
> df = data.frame(matrix(rnorm(20), nrow=10))
> df
X1 X2
1 0.7091409 -1.4061361
2 -1.1334614 -0.1973846
3 2.3343391 -0.4385071
4 -0.9040278 -0.6593677
5 0.4180331 -1.2592415
6 0.7572246 -0.5463655
7 -0.8996483 0.4231117
8 ...
Associativity of “in” in Python?
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123
1 in [] in 'a' is evaluated as (1 in []) and ([] in 'a').
Since the first condition (1 in [])...
How can I get the intersection, union, and subset of arrays in Ruby?
...union
def |(other)
@set | other.set
end
end
x = MultiSet.new([1,1,2,2,3,4,5,6])
y = MultiSet.new([1,3,5,6])
p x - y # [2,2,4]
p x & y # [1,3,5,6]
p x | y # [1,2,3,4,5,6]
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|
impro...
Difference between numpy.array shape (R, 1) and (R,)
... how to interpret the data buffer.
For example, if we create an array of 12 integers:
>>> a = numpy.arange(12)
>>> a
array([ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11])
Then a consists of a data buffer, arranged something like this:
┌────┬────┬──...
Subscripts in plots in R
...to write subscripts in the title or the subtitle in R.
How can I write v 1,2 with 1,2 as subscripts?
6 Answers
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How can I obtain the element-wise logical NOT of a pandas Series?
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274
To invert a boolean Series, use ~s:
In [7]: s = pd.Series([True, True, False, True])
In [8]:...
What does “@@ -1 +1 @@” mean in Git's diff output?
...time
+++ to-file to-file-modification-time
The time stamp looks like 2002-02-21 23:30:39.942229878 -0800 to indicate the date, time with fractional seconds, and time zone. The fractional seconds are omitted on hosts that do not support fractional time stamps.
You can change the header's c...
Filtering a list based on a list of booleans
...ss:
>>> from itertools import compress
>>> list_a = [1, 2, 4, 6]
>>> fil = [True, False, True, False]
>>> list(compress(list_a, fil))
[1, 4]
Timing comparisons(py3.x):
>>> list_a = [1, 2, 4, 6]
>>> fil = [True, False, True, False]
>>>...
Clojure 1.2.1/1.3/1.4 'proxy generated in Grails 2.0.0 runtime fails. 1.2.0 is fine
I'm working on extending the Grails Clojure plugin in Grails 2.0.0 (and 2.1.0-SNAPSHOT) and I wanted to update it to Clojure 1.3.0 and add clojure.tools.logging .
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finding and replacing elements in a list
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266
>>> a= [1, 2, 3, 4, 5, 1, 2, 3, 4, 5, 1]
>>> for n, i in enumerate(a):
... ...