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How do I determine the target architecture of static library (.a) on Mac OS X?
...ibiodbc.a
Architectures in the fat file: /usr/lib/libiodbc.a are: x86_64 i386 ppc
% lipo -info libnonfatarchive.a
input file libnonfatarchive.a is not a fat file
Non-fat file: libnonfatarchive.a is architecture: i386
%
sha...
Why do we have map, fmap and liftM?
...onad without also being an instance of Functor.
-- Typeclassopedia, page 33
Edit: agustuss's history of map and fmap:
That's not actually how it happens. What happened was that the type of map was generalized to cover Functor in Haskell 1.3. I.e., in Haskell 1.3 fmap was called map. This chan...
Find difference between timestamps in seconds in PostgreSQL
I have a table in PostgreSQL 8.3 with 2 timestamp columns. I would like to get the difference between these timestamps in seconds. Could you please help me how to get this done?
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Why are my basic Heroku apps taking two seconds to load?
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edited Jan 20 '18 at 22:03
Tomáš Hübelbauer
4,13844 gold badges4242 silver badges7474 bronze badges
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deleting rows in numpy array
...mpy.delete method.
Suppose I have the following array x:
x = array([[1,2,3],
[4,5,6],
[7,8,9]])
To delete the first row, do this:
x = numpy.delete(x, (0), axis=0)
To delete the third column, do this:
x = numpy.delete(x,(2), axis=1)
So you could find the indices of the rows ...
Convert column classes in data.table
...rter)]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.character:
dtnew <- dt[, lapply(....
Install MySQL on Ubuntu without a password prompt
...
432
sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password password your...
Does Internet Explorer support pushState and replaceState?
... section on history.
Summary - IE9: no, IE10: yes (as of platform preview 3)
The first Release Candidate of IE9 (released 10th Feb 2011) does not support history.pushState or history.replaceState. Generally no new features are added after a product gets to RC stage so it is very unlikely that the ...
How do I convert a NSString into a std::string?
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Rails hidden field undefined method 'merge' error
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– Augustin Riedinger
Sep 24 '14 at 13:30
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