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Average of 3 long integers
I have 3 very large signed integers.
12 Answers
12
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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
... from pandas import *
In [2]: def calculate(x):
...: return x*2, x*3
...:
In [3]: df = DataFrame({'a': [1,2,3], 'b': [2,3,4]})
In [4]: df
Out[4]:
a b
0 1 2
1 2 3
2 3 4
In [5]: df["A1"], df["A2"] = zip(*df["a"].map(calculate))
In [6]: df
Out[6]:
a b A1 A2
0 1 2 2...
Is R's apply family more than syntactic sugar?
... makeSOCKcluster(c("localhost","localhost"))
parSapply(cl, 1:20, get("+"), 3)
This example uses a socket cluster, for which no additional software needs to be installed; otherwise you will need something like PVM or MPI (see Tierney's clustering page). snow has the following apply functions:
par...
How can I loop through a List and grab each item?
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answered Sep 18 '13 at 3:08
Simon WhiteheadSimon Whitehead
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Could not load file or assembly 'Newtonsoft.Json' or one of its dependencies. Manifest definition do
...
32 Answers
32
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Comparing strings with == which are declared final in Java
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232
When you declare a String (which is immutable) variable as final, and initialize it with a comp...
How to normalize an array in NumPy?
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3
Thanks for the answer but are you sure that sklearn.preprocessing.normalize works also with vector of shape=(n,) or (n,1) ? I am having som...
How to format a number as percentage in R?
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Richie CottonRichie Cotton
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How do you know when to use fold-left and when to use fold-right?
... you use a left fold. Example (haskell-style pseudocode)
foldl (-) [1, 2, 3] == (1 - 2) - 3 == 1 - 2 - 3 // - is left-associative
If your operator is right-associative (right fold), the parentheses would be set like this:
A x (B x (C x D))
Example: Cons-Operator
foldr (:) [] [1, 2, 3] == 1 : ...
Google Maps API v3: How do I dynamically change the marker icon?
Using Google Maps API v3, how do I programmatically change the marker icon?
5 Answers
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