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Why `null >= 0 && null
...ncrements the value of a variable by 1 if its type is number and assigns 0 to the variable if not, where the variable is initially null or undefined .
...
CSS3 Transparency + Gradient
...round-image: -webkit-gradient(
linear, left top, left bottom, from(rgba(50,50,50,0.8)),
to(rgba(80,80,80,0.2)), color-stop(.5,#333333)
);
(src)
/* mozilla example - FF3.6+ */
background-image: -moz-linear-gradient(
rgba(255, 255, 255, 0.7) 0%, rgba(255, 255, 255, 0) 95%
);
(src)
Apparent...
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 ...
Should I return EXIT_SUCCESS or 0 from main()?
...eing conflicting answers: should the main routine of a C++ program return 0 or EXIT_SUCCESS ?
8 Answers
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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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How to drop rows of Pandas DataFrame whose value in a certain column is NaN
...
AMC
2,22966 gold badges1010 silver badges2828 bronze badges
answered Nov 16 '12 at 9:34
eumiroeumiro
1...
How do SO_REUSEADDR and SO_REUSEPORT differ?
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1680
+100
Welcome ...
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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Why is it slower to iterate over a small string than a small list?
...
TL;DR
The actual speed difference is closer to 70% (or more) once a lot of the overhead is removed, for Python 2.
Object creation is not at fault. Neither method creates a new object, as one-character strings are cached.
The difference is unobvious, but is likely created f...
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 ...