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Difference between declaring variables before or in loop?
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260
Which is better, a or b?
From a performance perspective, you'd have to measure it. (And in my o...
Pandas every nth row
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207
I'd use iloc, which takes a row/column slice, both based on integer position and following norm...
leading zeros in rails
...eld, if the user enters "1" I would like Rails to automatically pad it to "01" before saving it to the database. Also for the min field if the user enter "0" it should put in as "00".
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Why does ++[[]][+[]]+[+[]] return the string “10”?
This is valid and returns the string "10" in JavaScript ( more examples here ):
9 Answers
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.NET String.Format() to add commas in thousands place for a number
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String.Format("{0:n}", 1234); // Output: 1,234.00
String.Format("{0:n0}", 9876); // No digits after the decimal point. Output: 9,876
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Append value to empty vector in R?
...et.seed(21)
values <- sample(letters, 1e4, TRUE)
vector <- character(0)
# slow
system.time( for (i in 1:length(values)) vector[i] <- values[i] )
# user system elapsed
# 0.340 0.000 0.343
vector <- character(length(values))
# fast(er)
system.time( for (i in 1:length(values)) vec...
Is there a NumPy function to return the first index of something in an array?
...mensions and it contained your item at two locations then
array[itemindex[0][0]][itemindex[1][0]]
would be equal to your item and so would
array[itemindex[0][1]][itemindex[1][1]]
numpy.where
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Accessing items in an collections.OrderedDict by index
...> d.items()
[('foo', 'python'), ('bar', 'spam')]
>>> d.items()[0]
('foo', 'python')
>>> d.items()[1]
('bar', 'spam')
Note for Python 3.X
dict.items would return an iterable dict view object rather than a list. We need to wrap the call onto a list in order to make the indexing...
Can someone give an example of cosine similarity, in a very simple, graphical way?
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10 Answers
10
Active
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Append a NumPy array to a NumPy array
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answered Mar 19 '12 at 18:01
endolithendolith
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