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Blocks and yields in Ruby
...trary segments of code.
When a method expects a block, it invokes it by calling the yield function.
This is very handy, for instance, to iterate over a list or to provide a custom algorithm.
Take the following example:
I'm going to define a Person class initialized with a name, and provide a ...
Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
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What if I have a separate called Counts and instead of count the rows of the grouped type, I need to add along the column Counts.
– Abhishek Bhatia
Oct 2 '17 at 21:28
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ggplot with 2 y axes on each side and different scales
I need to plot a bar chart showing counts and a line chart showing rate all in one chart, I can do both of them separately, but when I put them together, I scale of the first layer (i.e. the geom_bar ) is overlapped by the second layer (i.e. the geom_line ).
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How to un-escape a backslash-escaped string?
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Basically for Python3 you want print(b"Hello,\nworld!".decode('unicode_escape'))
– ChristopheD
Apr 7 '15 at 8:35
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AsyncTask threads never die
...uriosity, why is it designed like that? Why not just end the threads after all of the methods have returned?
– Computerish
Jun 20 '10 at 2:38
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How do I delete a fixed number of rows with sorting in PostgreSQL?
...erm row identifier.
There's also oid but that only exists if you specifically ask for it when you create the table.
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Get GPS location from the web browser
...egrated Google Maps, I need to fill the 'From' field of Google Maps dynamically.
6 Answers
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Prevent linebreak after
...y:inline;
OR
float:left;
OR
display:inline-block; -- Might not work on all browsers.
What is the purpose of using a div here? I'd suggest a span, as it is an inline-level element, whereas a div is a block-level element.
Do note that each option above will work differently.
display:inline; w...
How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...of PostgreSQL
In old versions of PostgreSQL (prior to 8.x?) you had to do all the dirty work. The following sequence of commands should do the trick:
ALTER TABLE test1 ADD COLUMN id INTEGER;
CREATE SEQUENCE test_id_seq OWNED BY test1.id;
ALTER TABLE test ALTER COLUMN id SET DEFAULT nextval('...
What is the effect of encoding an image in base64?
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Here's a really helpful overview of when to base64 encode and when not to by David Calhoun.
Basic answer = gzipped base64 encoded files will be roughly comparable in file size to standard binary (jpg/png). Gzip'd binary files will ha...