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How to check a string for specific characters?
...can I check if a string has several specific characters in it using Python 2?
5 Answers
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Pandas dataframe get first row of each group
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248
>>> df.groupby('id').first()
value
id
1 first
2 first
3 first
4...
Get a specific bit from byte
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Easy. Use a bitwise AND to compare your number with the value 2^bitNumber, which can be cheaply calculated by bit-shifting.
//your black magic
var bit = (b & (1 << bitNumber-1)) != 0;
EDIT: To add a little more detail because there are a lot of similar answers with no expla...
How to use/install gcc on Mac OS X 10.8 / Xcode 4.4
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423
Update:
You can now just run the following command from your terminal:
xcode-select --install...
How do you know when to use fold-left and when to use fold-right?
...re, 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...
“ValueError: zero length field name in format” error in Python 3.0,3.1,3.2
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I'm gonna guess that you are running python 2.6 by accident somehow.
This feature is only available for at least 3.1 if you are using python 3, or 2.7 if you are using python 2.
share
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What's the simplest way to test whether a number is a power of 2 in C++?
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edited Dec 2 '15 at 3:59
jbranchaud
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Pandas convert dataframe to array of tuples
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211
How about:
subset = data_set[['data_date', 'data_1', 'data_2']]
tuples = [tuple(x) for x in s...
How can I obtain an 'unbalanced' grid of ggplots?
..., arrangeGrob(p,p,p, heights=c(3/4, 1/4, 1/4), ncol=1),
ncol=2)
Edit (07/2015): with v>2.0.0 you can use the layout_matrix argument,
grid.arrange(p,p,p,p, layout_matrix = cbind(c(1,1,1), c(2,3,4)))
shar...
How does Python 2 compare string and int? Why do lists compare as greater than numbers, and tuples g
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2 Answers
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