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“Inner exception” (with traceback) in Python?
...
138
Python 2
It's simple; pass the traceback as the third argument to raise.
import sys
class MyE...
What is the most efficient/elegant way to parse a flat table into a tree?
...id, descendant_id) VALUES
(1,1), (1,2), (1,4), (1,6),
(2,2), (2,4),
(3,3), (3,5),
(4,4),
(5,5),
(6,6);
Now you can get a tree starting at node 1 like this:
SELECT f.*
FROM FlatTable f
JOIN ClosureTable a ON (f.id = a.descendant_id)
WHERE a.ancestor_id = 1;
The output (in MySQL c...
Difference between List, List, List, List, and List
...Could e.g. be used by a method that is returning the length of the list.
3) T, E and U are the same, but people tend to use e.g. T for type, E for Element, V for value and K for key. The method that compiles says that it took an array of a certain type, and returns an array of the same type.
4) Y...
Pandas conditional creation of a series/dataframe column
...s
Set Type color
0 Z A green
1 Z B green
2 X B red
3 Y C red
If you have more than two conditions then use np.select. For example, if you want color to be
yellow when (df['Set'] == 'Z') & (df['Type'] == 'A')
otherwise blue when (df['Set'] == 'Z') & (df[...
Creating a new dictionary in Python
... |
edited Nov 8 '15 at 3:49
poolie
8,03611 gold badge3838 silver badges6666 bronze badges
answered De...
How to pass command line arguments to a rake task
...
389
Options and dependencies need to be inside arrays:
namespace :thing do
desc "it does a thing...
How does the Brainfuck Hello World actually work?
...ctual cell.
Take a look at ASCII table. For example, decimal code of ! is 33, while a is 97.
Well, lets imagine your BF program memory looks like:
...[0][0][*0*][0][0]...
Assuming standard input stands for a, if you use comma , operator, what BF does is read a decimal ASCII code 97 to memory:
...
How to handle exceptions in a list comprehensions?
...rtelli
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14
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Gem::LoadError for mysql2 gem, but it's already in Gemfile
...ith rails 4.1.5) try using this version of mysql2:
gem 'mysql2', '~> 0.3.18'
Apparently mysql2 isn't still compatible with newer version of rails because rails 4.2.4 is pretty new as the time of answering this question by me 8 September 2015 so use the above line in your Gem file and run:
bu...
Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
...t once. This should give you the result you need:
df[['col1', 'col2', 'col3', 'col4']].groupby(['col1', 'col2']).agg(['mean', 'count'])
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