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Combining two Series into a DataFrame in pandas
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I think concat is a nice way to do this. If they are present it uses the name attributes of the Series as the columns (otherwise it simply numbers them):
In [1]: s1 = pd.Series([1, 2], index=['A', 'B'], name='s1')
In [2]: s2 = pd.Series([3, 4], index...
How to determine the screen width in terms of dp or dip at runtime in Android?
I need to code the layout of the android widgets using dip/dp (in java files). At runtime if I code,
int pixel=this.getWindowManager().getDefaultDisplay().getWidth() ;
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How to compare DateTime in C#?
...WriteLine("{0} {1} {2}", date1, relationship, date2);
// The example displays the following output:
// 8/1/2009 12:00:00 AM is earlier than 8/1/2009 12:00:00 PM
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What is the maven-shade-plugin used for, and why would you want to relocate Java packages?
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Uber JAR, in short, is a JAR containing everything.
Normally in Maven, we rely on dependency management. An artifact contains only the classes/resources of itself. Maven will be responsible to find out all artifacts (JARs etc) that the project depending on when the ...
How do I get ruby to print a full backtrace instead of a truncated one?
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Exception#backtrace has the entire stack in it:
def do_division_by_zero; 5 / 0; end
begin
do_division_by_zero
rescue => exception
puts exception.backtrace
raise # always reraise
end
(Inspired by Peter Cooper's Ruby Inside blog)
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Getting a better understanding of callback functions in JavaScript
...not understanding the best implementation to do that. I'm looking for a very basic example, like this:
8 Answers
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Postgresql GROUP_CONCAT equivalent?
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This is probably a good starting point (version 8.4+ only):
SELECT id_field, array_agg(value_field1), array_agg(value_field2)
FROM data_table
GROUP BY id_field
array_agg returns an array, but you can CAST that to text and edit as needed ...
Safely remove migration In Laravel
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I accidentally created a migration with a bad name (command: php artisan migrate:make). I did not run (php artisan migrate) the migration, so I decided to remove it.
My steps:
Manually delete the migration file under app/database/migrat...
How can I tell where mongoDB is storing data? (its not in the default /data/db!)
My host came with a mongodb instance and there is no /db directory so now I am wondering what I can do to find out where the data is actually being stored.
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MySQL dump by query
Is it possible to do mysqldump by single SQL query ?
9 Answers
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