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How to drop columns by name in a data frame
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389
You should use either indexing or the subset function. For example :
R> df <- data.fram...
List of lists changes reflected across sublists unexpectedly
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593
When you write [x]*3 you get, essentially, the list [x, x, x]. That is, a list with 3 references...
How can I sort a dictionary by key?
What would be a nice way to go from {2:3, 1:89, 4:5, 3:0} to {1:89, 2:3, 3:0, 4:5} ?
I checked some posts but they all use the "sorted" operator that returns tuples.
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Numpy: Divide each row by a vector element
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answered Oct 26 '13 at 2:38
JoshAdelJoshAdel
53.3k2222 gold badges125125 silver badges126126 bronze badges
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Iterate a list with indexes in Python
...ld swear I've seen the function (or method) that takes a list, like this [3, 7, 19] and makes it into iterable list of tuples, like so: [(0,3), (1,7), (2,19)] to use it instead of:
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Shuffle two list at once with same order
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You can do it as:
import random
a = ['a', 'b', 'c']
b = [1, 2, 3]
c = list(zip(a, b))
random.shuffle(c)
a, b = zip(*c)
print a
print b
[OUTPUT]
['a', 'c', 'b']
[1, 3, 2]
Of course, this was an example with simpler lists, but the adaptation will be the same for your case.
Hope it ...
finding and replacing elements in a list
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>>> a= [1, 2, 3, 4, 5, 1, 2, 3, 4, 5, 1]
>>> for n, i in enumerate(a):
... if i == 1:
... a[n] = 10
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>>> a
[10, 2, 3, 4, 5, 10, 2, 3, 4, 5, 10]
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If vs. Switch Speed
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answered Jan 14 '09 at 23:16
Konrad RudolphKonrad Rudolph
461k118118 gold badges863863 silver badges11101110 bronze badges
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Easiest way to upgrade eclipse 3.7 to 4.2 (Juno)
So since Eclipse juno is based on 4.2 instead of 3.7, what is the easiest way to upgrade to it, short of installing a separate copy of juno and re-installing all my existing plugins from 3.7 into it?
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String formatting in Python 3
...at(self) # '<__main__.Player instance at 0x00BF7260>'
"games: {:>3}".format(player1.games) # 'games: 123'
"games: {:>3}".format(player2.games) # 'games: 4'
"games: {:0>3}".format(player2.games) # 'games: 004'
Note: As others pointed out, the new format does not supersede the ...