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Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...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 µs per loop
Note that you ...
What is The Rule of Three?
...r class X calls the destructors for X's direct [...] members
[n3126.pdf 12.4 §6]
Managing resources
So when should we declare those special member functions explicitly?
When our class manages a resource, that is,
when an object of the class is responsible for that resource.
That usually means the ...
Check if a JavaScript string is a URL
...+[a-z]{2,}|'+ // domain name
'((\\d{1,3}\\.){3}\\d{1,3}))'+ // OR ip (v4) address
'(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*'+ // port and path
'(\\?[;&a-z\\d%_.~+=-]*)?'+ // query string
'(\\#[-a-z\\d_]*)?$','i'); // fragment locator
return !!pattern.test(str);
}
...
How do I specify different layouts for portrait and landscape orientations?
...
204
Create a layout-land directory and put the landscape version of your layout XML file in that dir...
Processing Symbol Files in Xcode
...a specific CPU type. The currently CPU types needed are armv7 (e.g. iPhone 4, iPhone 4s), armv7s (e.g. iPhone 5) and arm64 (e.g. iPhone 5s).
So if you want to symbolicate a crash report that happened on an iPhone 5 with armv7s and only have the symbols for armv7 for that specific iOS version, Xcode...
How do I find numeric columns in Pandas?
...exclude. So isNumeric would look like:
numerics = ['int16', 'int32', 'int64', 'float16', 'float32', 'float64']
newdf = df.select_dtypes(include=numerics)
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How do I create a URL shortener?
...ou just do a reverse lookup in your alphabet.
e9a62 will be resolved to "4th, 61st, and 0th letter in the alphabet".
e9a62 = [4,61,0] = 4×622 + 61×621 + 0×620 = 1915810
Now find your database-record with WHERE id = 19158 and do the redirect.
Example implementations (provided by commenters)
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Creating an R dataframe row-by-row
...de in R.
If you can, allocate your entire data.frame up front:
N <- 1e4 # total number of rows to preallocate--possibly an overestimate
DF <- data.frame(num=rep(NA, N), txt=rep("", N), # as many cols as you need
stringsAsFactors=FALSE) # you don't know levels yet...
if A vs if A is not None:
...
answered Oct 19 '11 at 4:09
Greg HewgillGreg Hewgill
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Get the current script file name
...
417
Just use the PHP magic constant __FILE__ to get the current filename.
But it seems you want t...