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  • slice - How slicing in Python works - Stack Overflow
    Explain Python's slice notation In short, the colons (:) in subscript notation (subscriptable[subscriptarg]) make slice notation, which has the optional arguments start, stop, and step: sliceable[start:stop:step] Python slicing is a computationally fast way to methodically access parts of your data
  • list - what does [::-1] mean in python - slicing? - Stack Overflow
    Python interpreter is smart enough to convert a slice of range into another range This is an optimization, ranges are generators They are dynamic, i e they don't hold all the elements in the memory at once It the interpreter you are using worked step-by-step, it would have to generate whole list, just to be able to iterate in a reverse order
  • What is :: (double colon) in Python when subscripting sequences?
    We can then open up slice objects as: s = slice(1, 2, 3) assert s start == 1 assert s stop == 2 assert s step == 3 This is notably used in Numpy to slice multi-dimensional arrays in any direction Of course, any sane API should use ::3 with the usual "every 3" semantic The related Ellipsis is covered further at: What does the Ellipsis object do?
  • python - How to slice a pandas DataFrame by position . . . - Stack Overflow
    I have a Pandas Data Frame object that has 1000 rows and 10 columns I would simply like to slice the Data Frame and take the first 10 rows How can I do this? I've been trying to use this: gt; g
  • python - How to take column-slices of dataframe in pandas - Stack Overflow
    I'd like to slice this dataframe in two dataframes: one containing the columns a and b and one containing the columns c, d and e It is not possible to write something like observations = data[:'c'] features = data['c':]
  • What does the slice() function do in Python? - Stack Overflow
    Whenever some other code uses slice notation on your an instance of your class Python will call your __getitem__ method with a slice object (Older versions of Python used a __getslice__ method instead of this approach, but that has been deprecated since 2 6, and support for it is gone completely in Python 3 ) –
  • python - Slicing a dictionary - Stack Overflow
    Thanks for the timings! {k:d[k] for k in l} is reasonably readable for someone with some experience (and more so than the slightly more complicated version in my question), but something like d intersect(l) would be nicer still: There's a dictionary, a list, and I'm doing something to them, no need to mention k three times, which is neither input nor output of the operation
  • How to Split Image Into Multiple Pieces in Python
    python -m pip install image_slicer Copy the image you want to slice into the Python root directory, open a python shell (not the "command line"), and enter these commands: import image_slicer image_slicer slice('huge_test_image png', 14) The beauty of this module is that it Is installed in python ; Can invoke an image split with two lines of code
  • How to slice a list in Python - Stack Overflow
    To trim in-place, use del on a slice; e g del listobj[-x:] will remove the last x elements from the list object – Martijn Pieters Commented Aug 18, 2016 at 14:09
  • Slicing a list using a variable, in Python - Stack Overflow
    Given a list a = range(10) You can slice it using statements such as a[1] a[2:4] However, I want to do this based on a variable set elsewhere in the code I can easily do this for the first one





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