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Why were pandas merges in python faster than data.table merges in R in 2012?
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It looks like Wes may have discovered a known issue in data.table when the number of unique strings (levels) is large: 10,000.
Does Rprof() reveal most of the time spent in the call sortedmatch(levels(i[[lc]]), levels(x[[rc]])? This isn't really the join itself (t...
Custom views with Storyboard
...Document Outline and you can hook up actions and references there too:
Now, the problem that remains is that you can't actually see the view no matter how many times you try to click or double click, which would defeat the whole purpose of putting it in the same storyboard. Fortunately there are...
How to redirect output of an already running process [duplicate]
... ps aux | grep cat
rjc 6760 0.0 0.0 1580 376 pts/5 S+ 15:31 0:00 cat
Now check the file handles it has open:
$ ls -l /proc/6760/fd
total 3
lrwx—— 1 rjc rjc 64 Feb 27 15:32 0 -> /dev/pts/5
l-wx—— 1 rjc rjc 64 Feb 27 15:32 1 -> /tmp/foo1
lrwx—— 1 rjc rjc 64 Feb 27 15:32 2 ->...
How can I find the number of days between two Date objects in Ruby?
...conds, such as this example
2.0.0-p195 :017 > a_date_time = DateTime.now
=> #<DateTime: 2013-12-31T12:23:03-08:00 ((2456658j,73383s,725757000n),-28800s,2299161j)>
2.0.0-p195 :018 > b_date_time = DateTime.now-20
=> #<DateTime: 2013-12-11T12:23:06-08:00 ((2456638j,73386s,699...
Javascript library for human-friendly relative date formatting [closed]
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Since I wrote this answer, a well known library available is moment.js.
There are libraries available, but it is trivial to implement it yourself. Just use a handful of conditions.
Assume date is an instantiated Date object for the time you want to make a ...
How do I force git to use LF instead of CR+LF under windows?
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By now the .gitattributes lines should read: *.txt text eol=lf as per git-scm.com/docs/gitattributes
– grandchild
Jan 9 at 16:41
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Is it good practice to NULL a pointer after deleting it?
... Imagaine a mainainer comming back a year later and seeing foo deleted. He now believes he can re-use the pointer unfortunately he may miss the second delete (it may not even be in the same function) and now the re-use of the pointer now gets trashed by the second delete. Any access after the second...
How do I get the current Date/time in DD/MM/YYYY HH:MM format?
... assumed you meant HH:MM instead of HH:SS, but it's easy to change):
Time.now.strftime("%d/%m/%Y %H:%M")
#=> "14/09/2011 14:09"
Updated for the shifting:
d = DateTime.now
d.strftime("%d/%m/%Y %H:%M")
#=> "11/06/2017 18:11"
d.next_month.strftime("%d/%m/%Y %H:%M")
#=> "11/07/2017 18:11"
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Specifying rails version to use when creating a new application
... that having Rails 3 installed fails for 2.3.5 -- Just tested on Mac OS X Snow Leopard with these modules installed:rails (3.0.5, 2.3.5, 2.2.2, 1.2.6)
– Mike
May 2 '11 at 19:41
13
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What does the JSLint error 'body of a for in should be wrapped in an if statement' mean?
...ethods. Lots of libraries do this.
However, let's look at how for in works now:
var listeners = ["a", "b", "c"];
for (o in listeners) {
console.log(o);
}
//prints:
// 0
// 1
// 2
// filter_0
Do you see? It suddenly thinks filter_0 is another array index. Of course, it is not really a nume...