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Check for installed packages before running install.packages() [duplicate]
... computers. One of its lines contains the install.packages("xtable") command.
16 Answers
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Where am I? - Get country
An android mobile actually does know quite well where it is - but is there a way of retrieving the country by something like a country code?
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Saving vim macros
...copy/paste registers so you can paste it as normal with the "xp or "xP commands in normal mode.
To save it you open up .vimrc and paste the contents, then the register will be around the next time you start vim.
The format is something like:
let @q = 'macro contents'
Be careful of quotes, though...
How do I get the current Date/time in DD/MM/YYYY HH:MM format?
How can I get the current date and time in DD/MM/YYYY HH:MM format and also increment the month?
4 Answers
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How to scroll to specific item using jQuery?
... element.scrollIntoView() - that is all that is required. Animation is standardised. See developer.mozilla.org/en-US/docs/Web/API/Element/scrollIntoView
– WickyNilliams
Feb 26 '16 at 11:46
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Getting the docstring from a function
... BTW: This technique works with builtin functions as well as modules and classes (test help() with objects too - might also work). This makes your python shell an interactive help shell!
– Daren Thomas
Apr 3 '09 at 9:24
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How do I make class methods / properties in Swift?
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They are called type properties and type methods and you use the class or static keywords.
class Foo {
var name: String? // instance property
static var all = [Foo]() // static type property
class var comp: Int { // computed ...
Rename specific column(s) in pandas
...' else x for x in df.columns]
Or, construct a mapping using a dictionary and perform the list-comprehension with it's get operation by setting default value as the old name:
col_dict = {'gdp': 'log(gdp)', 'cap': 'cap_mod'} ## key→old name, value→new name
df.columns = [col_dict.get(x, x) fo...
Make body have 100% of the browser height
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As an alternative to setting both the html and body element's heights to 100%, you could also use viewport-percentage lengths.
5.1.2. Viewport-percentage lengths: the ‘vw’, ‘vh’, ‘vmin’, ‘vmax’ units
The viewport-percentage lengths are relative to the...
Why doesn't delete set the pointer to NULL?
...tomatic setting of the pointer to NULL after delete is not part of the standard. If this gets taken care of then many of the crashes due to an invalid pointer would not occur. But having said that I can think of couple of reasons why the standard would have restricted this:
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