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Why were pandas merges in python faster than data.table merges in R in 2012?
....table has time series merge in mind. Two aspects to that: i) multi column ordered keys such as (id,datetime) ii) fast prevailing join (roll=TRUE) a.k.a. last observation carried forward.
I'll need some time to confirm as it's the first I've seen of the comparison to data.table as presented.
UPD...
Bootstrap 3: pull-right for col-lg only
...to create your own class with media queries. Bootstrap 3 already has float ordering for media breakpoints under Column Ordering: http://getbootstrap.com/css/#grid-column-ordering
The syntax for the class is col-<#grid-size>-(push|pull)-<#cols> where <#grid-size> is xs, sm, md or l...
How do I pass a method as a parameter in Python
...thodToRun()
return result
obj.method2(obj.method1)
Note: I believe a __call__() method does exist, i.e. you could technically do methodToRun.__call__(), but you probably should never do so explicitly. __call__() is meant to be implemented, not to be invoked from your own code.
If you wanted me...
Is gcc 4.8 or earlier buggy about regular expressions?
....
Seriously though, who though that shipping an implementation of regex_search that only does "return false" was a good idea?
It wasn't such a bad idea a few years ago, when C++0x was still a work in progress and we shipped lots of partial implementations. No-one thought it would remain unusab...
How to format strings in Java
...od, so you just have to pass the restURL like this
/customer/{0}/user/{1}/order
and add as many params as you need:
public String createURL (String restURL, Object ... params) {
return new MessageFormat(restURL).format(params);
}
You just have to call this method like this:
createU...
How to get number of entries in a Lua table?
...ole table with pairs(..).
function tablelength(T)
local count = 0
for _ in pairs(T) do count = count + 1 end
return count
end
Also, notice that the "#" operator's definition is a bit more complicated than that. Let me illustrate that by taking this table:
t = {1,2,3}
t[5] = 1
t[9] = 1
Ac...
How to pick just one item from a generator?
...ption if necessary, or use the default argument to next():
next(g, default_value)
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Difference between attr_accessor and attr_accessible
...ment: new(attrs) or update_attributes(attrs).
Here's a mass assignment:
Order.new({ :type => 'Corn', :quantity => 6 })
You can imagine that the order might also have a discount code, say :price_off. If you don't tag :price_off as attr_accessible you stop malicious code from being able to ...
How do I find the location of my Python site-packages directory?
...ysconfig module instead:
python3 -c 'import sysconfig; print(sysconfig.get_paths()["purelib"])'
The per user site-packages directory (PEP 370) is where Python installs your local packages:
python -m site --user-site
If this points to a non-existing directory check the exit status of Python and ...
Why is early return slower than else?
...e a theory for you.
I tried your code and get the same of results, without_else() is repeatedly slightly slower than with_else():
>>> T(lambda : without_else()).repeat()
[0.42015745017874906, 0.3188967452567226, 0.31984281521812363]
>>> T(lambda : with_else()).repeat()
[0.3600984...