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Re-ordering columns in pandas dataframe based on column name [duplicate]
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399
df = df.reindex(sorted(df.columns), axis=1)
This assumes that sorting the column names will ...
Rank function in MySQL
...INSERT INTO person VALUES (2, 'Jane', 20, 'F');
INSERT INTO person VALUES (3, 'Jack', 30, 'M');
INSERT INTO person VALUES (4, 'Bill', 32, 'M');
INSERT INTO person VALUES (5, 'Nick', 22, 'M');
INSERT INTO person VALUES (6, 'Kathy', 18, 'F');
INSERT INTO person VALUES (7, 'Steve', 36, 'M');
INSERT INT...
Most efficient way to prepend a value to an array
...-O but certainly using the unshift method is more concise:
var a = [1, 2, 3, 4];
a.unshift(0);
a; // => [0, 1, 2, 3, 4]
[Edit]
This jsPerf benchmark shows that unshift is decently faster in at least a couple of browsers, regardless of possibly different big-O performance if you are ok with mo...
Get decimal portion of a number with JavaScript
I have float numbers like 3.2 and 1.6 .
22 Answers
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What does this square bracket and parenthesis bracket notation mean [first1,last1)?
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234
A bracket means that end of the range is inclusive -- it includes the element listed. A parenth...
How do I detect the Python version at runtime? [duplicate]
I have a Python file which might have to support Python versions < 3.x and >= 3.x. Is there a way to introspect the Python runtime to know the version which it is running (for example, 2.6 or 3.2.x )?
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Simple way to create matrix of random numbers
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13 Answers
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Why isn't my Pandas 'apply' function referencing multiple columns working? [closed]
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381
Seems you forgot the '' of your string.
In [43]: df['Value'] = df.apply(lambda row: my_test(r...
Python and pip, list all versions of a package that's available?
...h 2020, many people have reported that yolk, installed via pip install yolk3k, only returns latest version. Chris's answer seems to have the most upvotes and worked for me)
The script at pastebin does work. However it's not very convenient if you're working with multiple environments/hosts because...
How do you detect Credit card type based on number?
...a card numbers start with a 4.
MasterCard: ^5[1-5][0-9]{5,}|222[1-9][0-9]{3,}|22[3-9][0-9]{4,}|2[3-6][0-9]{5,}|27[01][0-9]{4,}|2720[0-9]{3,}$ Before 2016, MasterCard numbers start with the numbers 51 through 55, but this will only detect MasterCard credit cards; there are other cards issued using t...