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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
...quote from the data.table FAQ 1.11 What is the difference between X[Y] and merge(X, Y)?
X[Y] is a join, looking up X's rows using Y (or Y's key if it has one) as an index.
Y[X] is a join, looking up Y's rows using X (or X's key if it has one)
merge(X,Y) does both ways at the same time....
What is the best way to do GUIs in Clojure?
...
I will humbly suggest Seesaw.
Here's a REPL-based tutorial that assumes no Java or Swing knowledge.
Seesaw's a lot like what @tomjen suggests. Here's "Hello, World":
(use 'seesaw.core)
(-> (frame :title "Hello"
:content "Hello, Seesaw"
:on-close :exit)
pack!
show!)
...
What is the difference between iterator and iterable and how to use them?
... and I'm really confused with iterator and iterable. Can anyone explain to me and give some examples?
13 Answers
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How do I change bash history completion to complete what's already on the line?
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Probably something like
# ~/.inputrc
"\e[A": history-search-backward
"\e[B": history-search-forward
or equivalently,
# ~/.bashrc
if [[ $- == *i* ]]
then
bind '"\e[A": history-search-backward'
bind '"\e[B": history-search-f...
Counting DISTINCT over multiple columns
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Too good suggestion. It avoided me to write unnecessary code to this.
– Avrajit Roy
Mar 9 '16 at 6:39
1
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How to find the mime type of a file in python?
Let's say you want to save a bunch of files somewhere, for instance in BLOBs. Let's say you want to dish these files out via a web page and have the client automatically open the correct application/viewer.
...
Submit form using a button outside the tag
... cannot do this without javascript.
Here's what the spec says
The elements used to create controls generally appear inside a FORM
element, but may also appear outside of a FORM element declaration
when they are used to build user interfaces. This is discussed in the
section on intrinsic ...
Why we should not use protected static in java
...uestion Is there a way to override class variables in Java?
The first comment with 36 upvotes was:
8 Answers
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Prevent browser caching of AJAX call result
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I use new Date().getTime(), which will avoid collisions unless you have multiple requests happening within the same millisecond:
$.get('/getdata?_=' + new Date().getTime(), function(data) {
console.log(data);
});
Edit: This answer is sever...
How to debug .htaccess RewriteRule not working
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Enter some junk value into your .htaccess
e.g. foo bar, sakjnaskljdnas
any keyword not recognized by htaccess
and visit your URL. If it is working, you should get a
500 Internal Server Error
Internal Server Error
The ...