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What do the numbers in a version typically represent (i.e. v1.9.0.1)?
...
200
In version 1.9.0.1:
1: Major revision (new UI, lots of new features, conceptual change, etc.)...
Why does (1 in [1,0] == True) evaluate to False?
...arison operator chaining here. The expression is translated to
(1 in [1, 0]) and ([1, 0] == True)
which is obviously False.
This also happens for expressions like
a < b < c
which translate to
(a < b) and (b < c)
(without evaluating b twice).
See the Python language documentat...
Is 0 a decimal literal or an octal literal?
...hat actually almost all integer literals in my code are octal, namely 0 .
3 Answers
...
Convert columns to string in Pandas
...taFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"0":"A","1":"A","2":"B"}'
Note: you can pass in a buffer/file to save this to, along with some other options...
...
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
>>>...
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...
Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
...) and actually use true and false.
In a C compiler, this is equivalent to 0 and 1.
(note that removing the parentheses will break that due to order of operations)
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...
Black transparent overlay on image hover with only CSS?
... the img element itself, see.
.image {
position: relative;
width: 400px;
height: 400px;
}
Give the child img element a width of 100% of the parent and add vertical-align:top to fix the default baseline alignment issues.
.image img {
width: 100%;
vertical-align: top;
}
As for th...
Pandas percentage of total with groupby
...swer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
'office_id': list(range(1, 7)) * 2,
'sales': [np.random.randint(100000, 999999)
for _ in range(12...
how to use sed, awk, or gawk to print only what is matched?
... tried * instead and I added p tag for printing match:
sed -n 's/^.*abc\([0-9]*\)xyz.*$/\1/p' example.txt
For matching at least one numeric character without +, I would use:
sed -n 's/^.*abc\([0-9][0-9]*\)xyz.*$/\1/p' example.txt
...