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Is it better to call ToList() or ToArray() in LINQ queries?
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Tim Schmelter
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answered May 1 '13 at 17:42
JaredParJaredPar
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Mapping two integers to one, in a unique and deterministic way
...sy to define a bijection f : Z -> N, like so:
f(n) = n * 2 if n >= 0
f(n) = -n * 2 - 1 if n < 0
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I do not want to inherit the child opacity from the parent in CSS
...e 'a' is the level of transparency.
So instead of:
background-color: rgb(0,0,255); opacity: 0.5;
use
background-color: rgba(0,0,255,0.5);
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Double vs. BigDecimal?
...s a certain precision. Working with doubles of various magnitudes (say d1=1000.0 and d2=0.001) could result in the 0.001 being dropped alltogether when summing as the difference in magnitude is so large. With BigDecimal this would not happen.
The disadvantage of BigDecimal is that it's slower, and ...
Pandas groupby: How to get a union of strings
..._csv(StringIO(data),sep='\s+')
In [5]: df
Out[5]:
A B C
0 1 0.749065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: object
When...
How to convert index of a pandas dataframe into a column?
...either:
df['index1'] = df.index
or, .reset_index:
df.reset_index(level=0, inplace=True)
so, if you have a multi-index frame with 3 levels of index, like:
>>> df
val
tick tag obs
2016-02-26 C 2 0.0139
2016-02-27 A 2 0.5577
2016-02-28 C ...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
...ions have worked for me, except the one posted by @4lberto . I'm on pandas 0.23.4 and python 3.6
– goelakash
Aug 25 '18 at 13:22
1
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What does {0} mean when initializing an object?
When {0} is used to initialize an object, what does it mean? I can't find any references to {0} anywhere, and because of the curly braces Google searches are not helpful.
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What is the difference between 127.0.0.1 and localhost
... still have to do an actual lookup of localhost somewhere.
If you use 127.0.0.1, then (intelligent) software will just turn that directly into an IP address and use it. Some implementations of gethostbyname will detect the dotted format (and presumably the equivalent IPv6 format) and not do a looku...
How do SO_REUSEADDR and SO_REUSEPORT differ?
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