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Split comma-separated strings in a column into separate rows
...solution,
and two additional variants of Jaap's data.table methods.
Overall 8 different methods were benchmarked on 6 different sizes of data frames using the microbenchmark package (see code below).
The sample data given by the OP consists only of 20 rows. To create larger data frames, these 20...
Where does 'Hello world' come from?
' hello, world ' is usually the first example for any programming language. I've always wondered where this sentence came from and where was it first used.
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How to check if a string contains a substring in Bash
...egex in a bash script, this worked perfectly!
– blast_hardcheese
Feb 14 '12 at 5:10
114
The =~ op...
sqlalchemy IS NOT NULL select
...
column_obj != None will produce a IS NOT NULL constraint:
In a column context, produces the clause a != b. If the target is None, produces a IS NOT NULL.
or use isnot() (new in 0.7.9):
Implement the IS NOT operator.
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How do I run a Java program from the command line on Windows?
...ent directory is the default classpath, so you don't have to set -cp . manually.
– Artur Czajka
Nov 6 '16 at 0:51
2
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Turning live() into on() in jQuery
My application has dynamically added Dropdowns. The user can add as many as they need to.
5 Answers
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Is an index needed for a primary key in SQLite?
...x be explicitly created for it as well? SQLite does not appear to automatically create an index for a primary key column, but perhaps it indexes it anyway, given its purpose? (I will be searching on that column all the time).
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Converting a Pandas GroupBy output from Series to DataFrame
...1.index
Out[20]:
MultiIndex([('Alice', 'Seattle'), ('Bob', 'Seattle'), ('Mallory', 'Portland'),
('Mallory', 'Seattle')], dtype=object)
Perhaps you want something like this?
In [21]: g1.add_suffix('_Count').reset_index()
Out[21]:
Name City City_Count Name_Count
0 Alice S...
How to define @Value as optional
...swered Jan 8 '18 at 13:23
alonso_50alonso_50
9941010 silver badges1515 bronze badges
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Duplicate headers received from server
...invalidChars);
string replace = Regex.Replace(name, invalidReStr, "_").Replace(";", "").Replace(",", "");
return replace;
}
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