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How should one use std::optional?
I'm reading the documentation of std::experimental::optional and I have a good idea about what it does, but I don't understand when I should use it or how I should use it. The site doesn't contain any examples as of yet which leaves it harder for me to grasp the true concept of this object. When...
Maven: How to include jars, which are not available in reps into a J2EE project?
...l repository. If you create a script with a Maven invocation for each file and keep it alongside the jars, you (and anyone else with access) can easily install the jars (and associated pom files) to their local repository.
For example:
mvn install:install-file -Dfile=/usr/jars/foo.jar -DpomFile=/u...
Confusion between numpy, scipy, matplotlib and pylab
Numpy, scipy, matplotlib, and pylab are common terms among they who use python for scientific computation.
3 Answers
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How to prevent robots from automatically filling up a form?
...attacks) way of solving anti-spam is tracking the time between form-submit and page-load.
Bots request a page, parse the page and submit the form. This is fast.
Humans type in a URL, load the page, wait before the page is fully loaded, scroll down, read content, decide wether to comment/fill in th...
How to center a subview of UIView
I have a UIView inside a UIView m and I want the inner UIView to be always centered inside the outer one, without it having to resize the width and height.
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Accessing localhost:port from Android emulator
...ith the IP address "10.0.2.2".
This has been designed in this way by the Android team. So your webserver can perfectly run at localhost and from your Android app you can access it via "http://10.0.2.2:<hostport>".
If your emulator must access the internet through a proxy server, you can con...
Logical Operators, || or OR?
... no "better" but the more common one is ||. They have different precedence and || would work like one would expect normally.
See also: Logical operators (the following example is taken from there):
// The result of the expression (false || true) is assigned to $e
// Acts like: ($e = (false || true...
How can I get last characters of a string
...th - 1); // => "1"
This gets the characters starting at id.length - 5 and, since the second argument for .substr() is omitted, continues to the end of the string.
You can also use the .slice() method as others have pointed out below.
If you're simply looking to find the characters after the u...
Accessing items in an collections.OrderedDict by index
...ems method returns an interable dictionary view object rather than a list, and don't support slicing or indexing. So you'd have to turn it into a list first. docs.python.org/3.3/library/stdtypes.html#dict-views
– Peter DeGlopper
Jun 5 '13 at 21:51
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Creating a Pandas DataFrame from a Numpy array: How do I specify the index column and column headers
...g of a list of lists, representing a two-dimensional array with row labels and column names as shown below:
9 Answers
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