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How to access the last value in a vector?
... vector that is nested in a dataframe one or two levels. Is there a quick and dirty way to access the last value, without using the length() function? Something ala PERL's $# special var?
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Return multiple values in JavaScript?
... first: getFirstValue(),
second: getSecondValue(),
};
}
And to access them:
var values = getValues();
var first = values.first;
var second = values.second;
Or with ES6 syntax:
const {first, second} = getValues();
* See this table for browser compatibility. Basically, all mod...
Meaning of $? (dollar question mark) in shell scripts
...
This is the exit status of the last executed command.
For example the command true always returns a status of 0 and false always returns a status of 1:
true
echo $? # echoes 0
false
echo $? # echoes 1
From the manual: (acessible by calling man bash in your shell)
$?...
Generate random numbers following a normal distribution in C/C++
How can I easily generate random numbers following a normal distribution in C or C++?
18 Answers
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Transitioning from Windows Forms to WPF
...e now, I have been stuck with Windows Forms development (started with VB6, and has continued through to C# .NET 4.5), and I have pretty much hit the limit of what Windows Forms can do, both using pure .NET, and special effects with Native Code.
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Preferred order of writing latitude & longitude tuples in GIS services
When dealing with GIS source code you often need to write latitude and longitude coordinate tuples.
9 Answers
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How to merge dictionaries of dictionaries?
...for key in b:
if key in a:
if isinstance(a[key], dict) and isinstance(b[key], dict):
merge(a[key], b[key], path + [str(key)])
elif a[key] == b[key]:
pass # same leaf value
else:
raise Exception('Conflict at %...
How to Correctly Use Lists in R?
...st?) contemporary programming languages in widespread use have at least a handful of ADTs [abstract data types] in common, in particular,
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Convert a Git folder to a submodule retrospectively?
Quite often it is the case that you're writing a project of some kind, and after a while it becomes clear that some component of the project is actually useful as a standalone component (a library, perhaps). If you've had that idea from early on, then there's a fair chance that most of that code is ...
Finding the number of days between two dates
...I think returning a negative number of days provides relevant information. And you should be using $your_date-$now, if you want a future date to return a positive integer.
– Tim
Mar 2 '12 at 18:49
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