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What does each of the [y,n,q,a,d,/,K,j,J,g,e,?] stand for in context of git -p
...this hunk nor any of the remaining ones
a - stage this hunk and all later hunks in the file
d - do not stage this hunk nor any of the later hunks in the file
g - select a hunk to go to
/ - search for a hunk matching the given regex
j - leave thi...
dplyr: “Error in n(): function should not be called directly”
...ction" specification, like example below:
delay <- dplyr::summarise(by_tailnum,
count = n(),
dist = mean(distance, na.rm = TRUE),
delay = mean(arr_delay, na.rm = TRUE))
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improv...
Check if key exists and iterate the JSON array using Python
...
If all you want is to check if key exists or not
h = {'a': 1}
'b' in h # returns False
If you want to check if there is a value for key
h.get('b') # returns None
Return a default value if actual value is missing
h.get('b'...
jQuery `.is(“:visible”)` not working in Chrome
...n appended to a
document since it depends on the applicable styles.
All option elements are considered hidden, regardless of their
selected state.
During animations that hide an element, the element is considered
visible until the end of the animation. During animations to show an
...
Does ruby have real multithreading?
...ing
models.
(Unfortunately, only two of those 11 implementations are actually
ready for production use, but by the end of the year that number
will probably go up to four or five.) (Update: it's now 5: MRI, JRuby, YARV (the interpreter for Ruby 1.9), Rubinius and IronRuby).
The first implement...
How can I find the last element in a List?
...elp. Enumerable.Last will throw an exception if the list is empty. If you call Enumerable.LastOrDefault and pass a list of value types the default value will be returned if the list is empty. So if you get 0 back from a List<int> you won't know if the list was empty or the last value was 0. I...
Is it Linq or Lambda?
...
This is LINQ (using query syntax):
var _Results = from item in _List
where item.Value == 1
select item;
This is also LINQ (using method syntax):
var _Results = _List.Where(x => x.Value == 1);
It's interesting to note that bo...
Split code over multiple lines in an R script
...
Bah, comments are too small. Anyway, @Dirk is very right.
R doesn't need to be told the code starts at the next line. It is smarter than Python ;-) and will just continue to read the next line whenever it considers the statement as "not finished". ...
Performance optimization strategies of last resort [closed]
...erformance questions on this site already, but it occurs to me that almost all are very problem-specific and fairly narrow. And almost all repeat the advice to avoid premature optimization.
...
Using an if statement to check if a div is empty
...If a container has a very long HTML content?
– techie_28
Jun 17 '16 at 10:07
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