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Numpy how to iterate over columns of array?
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answered Apr 13 '12 at 21:59
tillstentillsten
11.5k33 gold badges2626 silver badges3737 bronze badges
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Convert numpy array to tuple
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161
>>> arr = numpy.array(((2,2),(2,-2)))
>>> tuple(map(tuple, arr))
((2, 2), (2...
How to not run an example using roxygen2?
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147
Use \dontrun{}
#'@examples
#'\dontrun{
#'geocode("3817 Spruce St, Philadelphia, PA 19104")
#'...
Appending an element to the end of a list in Scala
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List(1,2,3) :+ 4
Results in List[Int] = List(1, 2, 3, 4)
Note that this operation has a complexity of O(n). If you need this operation frequently, or for long lists, consider using another data type (e.g. a ListBuffer).
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Dynamically select data frame columns using $ and a character value
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185
You can't do that kind of subsetting with $. In the source code (R/src/main/subset.c) it state...
What are the aspect ratios for all Android phone and tablet devices?
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162
In case anyone wanted more of a visual reference:
Decimal approximations reference table:
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Filtering a list based on a list of booleans
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188
You're looking for itertools.compress:
>>> from itertools import compress
>>&g...
Find the extension of a filename in Ruby
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167
That's really basic stuff:
irb(main):002:0> accepted_formats = [".txt", ".pdf"]
=> [".t...
What are the correct version numbers for C#?
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12 Answers
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How to determine if a number is a prime with regex?
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119
You said you understand this part, but just to emphasize, the String generated has a length eq...