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How to drop rows of Pandas DataFrame whose value in a certain column is NaN
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AMC
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answered Nov 16 '12 at 9:34
eumiroeumiro
1...
Simplest way to profile a PHP script
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104
The PECL APD extension is used as follows:
<?php
apd_set_pprof_trace();
//rest of the scri...
Pandas index column title or name
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In [8]: df.index.name = 'foo'
In [9]: df.index.name
Out[9]: 'foo'
In [10]: df
Out[10]:
Column 1
foo
Apples 1
Oranges 2
Puppies 3
Ducks 4
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From inside of a Docker container, how do I connect to the localhost of the machine?
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30 Answers
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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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Why is it slower to iterate over a small string than a small list?
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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...
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 ...
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 do I check to see if a value is an integer in MySQL?
...lar expression. Simply do
select field from table where field REGEXP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just test for
ceil(field) = field
instead.
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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 ...