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Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...t_index().drop_duplicates(subset='index', keep='first').set_index('index')
1000 loops, best of 3: 1.54 ms per loop
>>> %timeit df3.groupby(df3.index).first()
1000 loops, best of 3: 580 µs per loop
>>> %timeit df3[~df3.index.duplicated(keep='first')]
1000 loops, best of 3: 307 µ...
Formatting floats without trailing zeros
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18 Answers
18
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Extract elements of list at odd positions
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Solution
Yes, you can:
l = L[1::2]
And this is all. The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Exp...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
Intrigued by this question about infinite loops in perl: while (1) Vs. for (;;) Is there a speed difference? , I decided to run a similar comparison in python. I expected that the compiler would generate the same byte code for while(True): pass and while(1): pass , but this is actually not the c...
How can I eliminate slow resolving/loading of localhost/virtualhost (a 2-3 second lag) on Mac OS X L
...nvironments on Mac OS X Lion (brand new macbook air purchased in January 2012), I have noticed that resolving to a virtual host is very slow (around 3 seconds) the first time but after that is fast as long as I continue loading it regularly.
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Which is better, number(x) or parseFloat(x)?
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318
The difference between parseFloat and Number
parseFloat/parseInt is for parsing a string, whil...
Append value to empty vector in R?
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212
Appending to an object in a for loop causes the entire object to be copied on every iteration, ...
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
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11 Answers
11
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Why modelVersion of pom.xml is necessary and always set to 4.0.0?
... A POM has to comply with a model. Let's say Maven 4 comes up with model 4.1. If you write your pom to comply with 4.1, it wouldn't be compatible with Maven 3 and model 4.0.0.
It's defined as a mandatory, possibly to enforce a specific XML model in case new models are defined.
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