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How do I retrieve the number of columns in a Pandas data frame?
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312
Like so:
import pandas as pd
df = pd.DataFrame({"pear": [1,2,3], "apple": [2,3,4], "orange": [...
How to echo or print an array in PHP?
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11 Answers
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How to get a variable name as a string in PHP?
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edited Nov 1 '08 at 1:11
answered Nov 1 '08 at 0:42
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Using build types in Gradle to run same app that uses ContentProvider on one device
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14 Answers
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For i = 0, why is (i += i++) equal to 0?
...; // i=0 because the ++ is a postfix operator and hasn't been executed
i + 1; // Note that you are discarding the calculation result
What actually happens is more involved than that - take a look at MSDN, 7.5.9 Postfix increment and decrement operators:
The run-time processing of a postfix inc...
How to check if one of the following items is in a list?
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Scala 2.8 breakOut
...e the best builder possible. For example, if I were to write Map('a' -> 1).map(_.swap), I'd like to get a Map(1 -> 'a') back. On the other hand, a Map('a' -> 1).map(_._1) can't return a Map (it returns an Iterable).
The magic of producing the best possible Builder from the known types of t...
How to create a temporary directory?
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answered Jan 8 '11 at 2:30
moinudinmoinudin
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How can I create a correlation matrix in R?
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104
An example,
d &lt- data.frame(x1=rnorm(10),
x2=rnorm(10),
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