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Blocks and yields in Ruby
I am trying to understand blocks and yield and how they work in Ruby.
10 Answers
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Add margin above top ListView item (and below last) in Android
This is a pretty fine question about the layout of items in a ListView in Android.
5 Answers
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How do I convert a pandas Series or index to a Numpy array? [duplicate]
...d for a conversion.
Note: This attribute is also available for many other pandas' objects.
In [3]: df['A'].values
Out[3]: Out[16]: array([1, 2, 3])
To get the index as a list, call tolist:
In [4]: df.index.tolist()
Out[4]: ['a', 'b', 'c']
And similarly, for columns.
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@Basic(optional = false) vs @Column(nullable = false) in JPA
What's the difference between @Basic(optional = false) and @Column(nullable = false) in JPA persistence?
2 Answers
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Can't stop rails server
I am new to rails and I am using an ubuntu machine and the rubymine IDE. The problem is that I am unable to stop the rails server. I tried to stop the server by killing the rails process. But, when I run pgrep -l rails , no such process is found. So, I am only able to kill ruby processes, but, the ...
When to use a key/value store such as Redis instead/along side of a SQL database?
...real-time data, such as session store, state database, statistics, caching and its advanced data structures offers versatility to many other scenarios.
Redis, however, isn't NoSQL replacement for classic relational databases since it doesn't support many standard features of RDBMS world such as que...
How can I get file extensions with JavaScript?
... Isn't it expensive to exec the regex twice?
– Andrew Hedges
Oct 11 '08 at 7:39
6
The highl...
Standardize data columns in R
I have a dataset called spam which contains 58 columns and approximately 3500 rows of data related to spam messages.
15 ...
Asynchronous Process inside a javascript for loop [duplicate]
...ronous operations are started. When they complete some time in the future and call their callbacks, the value of your loop index variable i will be at its last value for all the callbacks.
This is because the for loop does not wait for an asynchronous operation to complete before continuing on t...
What is the meaning of “$” sign in JavaScript
...from one of the popular JavaScript libraries (jQuery, ProtoType, mooTools, and so on).
There's nothing mysterious about the use of $ in JavaScript. $ is simply a valid JavaScript identifier.
JavaScript allows upper and lower letters, numbers, and $ and _. The $ was intended to be used for machine-...