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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
...where)
As a worked example:
import pandas as pd
>>> df
country
0 US
1 UK
2 Germany
3 China
>>> countries_to_keep
['UK', 'China']
>>> df.country.isin(countries_to_keep)
0 False
1 True
2 False
3 True
Name: country, dtype: bool
>>>...
Limit Decimal Places in Android EditText
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120
More elegant way would be using a regular expression ( regex ) as follows:
public class Decimal...
Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
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502
I would suggest using the duplicated method on the Pandas Index itself:
df3 = df3[~df3.index.du...
Formatting floats without trailing zeros
...
Me, I'd do ('%f' % x).rstrip('0').rstrip('.') -- guarantees fixed-point formatting rather than scientific notation, etc etc. Yeah, not as slick and elegant as %g, but, it works (and I don't know how to force %g to never use scientific notation;-).
...
Extract elements of list at odd positions
...l. 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
Explanation
The [1::2] at the end is just a notation for list slicing. Usually it is in the followi...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...ntents of True. In other words, True is reassignable:
Python 2.7 (r27:82508, Jul 3 2010, 21:12:11)
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> True = 4
>>> True
4
In Python 3.x it truly becomes a k...
Append value to empty vector in R?
...et.seed(21)
values <- sample(letters, 1e4, TRUE)
vector <- character(0)
# slow
system.time( for (i in 1:length(values)) vector[i] <- values[i] )
# user system elapsed
# 0.340 0.000 0.343
vector <- character(length(values))
# fast(er)
system.time( for (i in 1:length(values)) vec...
Which is better, number(x) or parseFloat(x)?
... same:
parseFloat('3'); // => 3
Number('3'); // => 3
parseFloat('1.501'); // => 1.501
Number('1.501'); // => 1.501
parseFloat('1e10'); // => 10000000000
Number('1e10'); // => 10000000000
So as long as you have standard numeric input, there's no difference. However, if your input...
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
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640
Difference between == and ===
The difference between the loosely == equal operator and the stri...
Why modelVersion of pom.xml is necessary and always set to 4.0.0?
... <modelVersion></modelVersion> of pom.xml is always set to 4.0.0.
4 Answers
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