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Grouping functions (tapply, by, aggregate) and the *apply family
...y). There are enough of them, though, that beginning useRs may have difficulty deciding which one is appropriate for their situation or even remembering them all. They may have a general sense that "I should be using an *apply function here", but it can be tough to keep them all straight at first.
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What is “origin” in Git?
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Can a single remote be an alias for multiple other remotes? What if I wanted one remote to push to multiple other remotes? For example, push to a primary repo, and a push to a backup repo? Would that be a reasonable thing to want in some situations? EDIT: There a...
How to do this using jQuery - document.getElementById(“selectlist”).value
..."selectlist").value
...it's worth noting that...
$('#selectlist')
...although 'equivalent' is not the same as...
document.getElementById("selectlist")
...as the former returns a jQuery object, not a DOM object.
To get the DOM object(s) from the jQuery one, use the following:
$('#selectlis...
Can Android do peer-to-peer ad-hoc networking?
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Although Android can't find and connect to ad-hoc networks it sure can connect to Access Points. So as a work-around you can turn your Wireless Card into an Access Point using, for example, Connectify.
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What's the difference between size_t and int in C++?
...usr/lib/gcc/x86_64-redhat-linux/5.3.1/include/stddef.h and therein it defaults to long unsigned int unless some other header file says otherwise.
– David Tonhofer
Jan 4 '16 at 19:38
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View a file in a different Git branch without changing branches
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git show somebranch:path/to/your/file
you can also do multiple files and have them concatenated:
git show branchA~10:fileA branchB^^:fileB
You do not have to provide the full path to the file, relative paths are acceptable e.g.:
git show branchA~10:../src/hello.c
If you want...
When should I use cross apply over inner join?
... t1
INNER JOIN
t2o
ON t2o.t1_id = t1.id
AND t2o.rn <= 3
, but this is less readable and probably less efficient.
Update:
Just checked.
master is a table of about 20,000,000 records with a PRIMARY KEY on id.
This query:
WITH q AS
(
SELECT *, ROW_NU...
iPhone UITextField - Change placeholder text color
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On iOS 7 I got this error: [<UITextField 0x11561d90> valueForUndefinedKey:]: this class is not key value coding-compliant for the key _field.
– i_am_jorf
Apr 9 '14 at 19:27
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makefile:4: *** missing separator. Stop
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$
ll:ll.c $
^Igcc -c -Wall -Werror -02 c.c ll.c -o ll $@ $<$
## the ^I above means a tab was there before the action part, so this line is ok .
$
clean :$
\rm -fr ll$
## see here there is no ^I which means , tab is not present ....
## in this case you need to open the file a...
Why does Html.ActionLink render “?Length=4”
... @Blah_Blah these days I don't use this at all, prefer writing my own <a> tags and just using Url.Action("Action", "Controller")
– roryf
May 13 '13 at 14:42
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