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What does the number in parentheses shown after Unix command names in manpages mean?
...
It's the section that the man page for the command is assigned to.
These are split as
General commands
System calls
C library functions
Special files (usually devices, those found in /dev) and drivers
File formats and conventions
Games and screensavers
Miscellanea
Sys...
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
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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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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 %...
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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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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python assert with and without parenthesis
...through a full interpreter, not through IDLE. Because assert is a keyword and not a function, you are actually passing in a tuple as the first argument and leaving off the second argument.
Recall that non-empty tuples evaluate to True, and since the assertion message is optional, you've essentiall...