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How to get nice formatting in the Rails console
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Its now YAML::ENGINE.yamler = 'psych'
– jumpa
Dec 5 '13 at 5:53
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What is the “right” way to iterate through an array in Ruby?
... may seem like a lot to remember, but don't worry, you can get by without knowing all of them. But as you start to learn and use the different methods, your code will become cleaner and clearer, and you'll be on your way to Ruby mastery.
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Is there an equivalent to CTRL+C in IPython Notebook in Firefox to break cells that are running?
.... Some processes within python handle SIGINTs more abruptly than others.
If you desperately need to stop something that is running in iPython Notebook and you started iPython Notebook from a terminal, you can hit CTRL+C twice in that terminal to interrupt the entire iPython Notebook server. This w...
Javascript checkbox onChange
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Well that's two clicks now isn't it?
– Rohmer
Dec 25 '17 at 7:37
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show 1 more comment
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Get generated id after insert
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The insert method returns the id of row just inserted or -1 if there was an error during insertion.
long id = db.insert(...);
where db is SQLiteDatabase.
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improve this answe...
What is attr_accessor in Ruby?
... Person.new
person.name = 'Dennis'
person.name # => "Dennis"
Awesome. Now we can write and read instance variable @name using reader and writer methods. Except, this is done so frequently, why waste time writing these methods every time? We can do it easier.
class Person
attr_reader :name
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What does .SD stand for in data.table in R
.SD looks useful but I do not really know what I am doing with it. What does it stand for? Why is there a preceding period (full stop). What is happening when I use it?
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The backend version is not supported to design database diagrams or tables
...ved and yes you were right - the 2012 version was already installed. Works now - thanks!
– JensOlsen
Aug 5 '14 at 20:07
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How to define a two-dimensional array?
...w, h = 8, 5;
Matrix = [[0 for x in range(w)] for y in range(h)]
You can now add items to the list:
Matrix[0][0] = 1
Matrix[6][0] = 3 # error! range...
Matrix[0][6] = 3 # valid
Note that the matrix is "y" address major, in other words, the "y index" comes before the "x index".
print Matrix[0]...
Calculating arithmetic mean (one type of average) in Python
...is a bad variable name because it looks so much like 1. Also, I would use if l rather than if len(l) > 0. See here
– zondo
Apr 13 '16 at 22:40
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