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How does C compute sin() and other math functions?
...on in C, contributed by IBM. Since October 2011, this is the code that actually runs when you call sin() on a typical x86-64 Linux system. It is apparently faster than the fsin assembly instruction. Source code: sysdeps/ieee754/dbl-64/s_sin.c, look for __sin (double x).
This code is very complex. N...
How to return result of a SELECT inside a function in PostgreSQL?
... -- potential ambiguity
END
$func$ LANGUAGE plpgsql;
Call:
SELECT * FROM word_frequency(123);
Explanation:
It is much more practical to explicitly define the return type than simply declaring it as record. This way you don't have to provide a column definition list with eve...
In Python, how do I index a list with another list?
...ng, either by integer, slice or index-list:
class Flexlist(list):
def __getitem__(self, keys):
if isinstance(keys, (int, slice)): return list.__getitem__(self, keys)
return [self[k] for k in keys]
Which, for your example, you would use as:
L = Flexlist(['a', 'b', 'c', 'd', 'e...
How to set JAVA_HOME in Linux for all users
...
For all users, I would recommend placing the following line in /etc/profile
export JAVA_HOME=$(readlink -f /usr/bin/javac | sed "s:/bin/javac::")
This will update dynamically and works well with the alternatives system. Do not...
rails i18n - translating text with links inside
...
en.yml
log_in_message_html: "This is a text, with a %{href} inside."
log_in_href: "link"
login.html.erb
<p> <%= t("log_in_message_html", href: link_to(t("log_in_href"), login_path)) %> </p>
...
How do I integrate Ajax with Django applications?
...ction, going to 127.0.0.1:8000/home will return the index.html and replace all the variables as asked (you probably know all this by now).
Now let's talk about AJAX. AJAX calls are client-side code that does asynchronous requests. That sounds complicated, but it simply means it does a request for y...
Extract month and year from a zoo::yearmon object
...
Ha thank you for this answer. It especially beats the other solutions when you want to do something like if(year(date1) > 2014){year(date1) <- year(date1) - 100}
– Vincent
Feb 10 '14 at 9:34
...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...:
SET @rUsername = ‘aname’ COLLATE utf8_unicode_ci; -- COLLATE added
CALL updateProductUsers(@rUsername, @rProductID, @rPerm);
Option 2: add COLLATE to the WHERE clause:
CREATE PROCEDURE updateProductUsers(
IN rUsername VARCHAR(24),
IN rProductID INT UNSIGNED,
IN rPerm VARCHAR(16...
Mimicking sets in JavaScript?
...the list is a little safer with this:
if (Object.prototype.hasOwnProperty.call(obj, A))
// put code here
}
because of potential conflict between built-in methods and/or properties on the base Object like the constructor property.
Sidebar on ES6: The current working version of ECMAScript 6 or s...
Unexpected results when working with very big integers on interpreted languages
...em will work in this case, since Python switches to long integers automatically if needed. And if that's not enough, it will switch to big integers as well.
– Alok Singhal
Aug 4 '13 at 19:37
...