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Array Size (Length) in C#
...
If it's a one-dimensional array a,
a.Length
will give the number of elements of a.
If b is a rectangular multi-dimensional array (for example, int[,] b = new int[3, 5];)
b.Rank
will give the number of dimensions (2) and
b.GetLe...
Calculate relative time in C#
...(ts.TotalSeconds);
if (delta < 1 * MINUTE)
return ts.Seconds == 1 ? "one second ago" : ts.Seconds + " seconds ago";
if (delta < 2 * MINUTE)
return "a minute ago";
if (delta < 45 * MINUTE)
return ts.Minutes + " minutes ago";
if (delta < 90 * MINUTE)
return "an hour ago";
if (...
Python division
... becoming a floating point number.
>>> 1 / 2
0
You should make one of them a float:
>>> float(10 - 20) / (100 - 10)
-0.1111111111111111
or from __future__ import division, which the forces / to adopt Python 3.x's behavior that always returns a float.
>>> from __futu...
PHP date yesterday [duplicate]
... very good answer, there are many ways to do it but you have the simple one, short and easy to understand ( + the OOP one for those interested in using more RAM ;)
– neofutur
Apr 12 '12 at 8:04
...
How do I pass a variable by reference?
... the method, the outer scope will know nothing about it, and after you're done, the outer reference will still point at the original object.
If you pass an immutable object to a method, you still can't rebind the outer reference, and you can't even mutate the object.
To make it even more clear, l...
How to get URL parameter using jQuery or plain JavaScript?
...{
return sParameterName[1] === undefined ? true : decodeURIComponent(sParameterName[1]);
}
}
};
And this is how you can use this function assuming the URL is,
http://dummy.com/?technology=jquery&blog=jquerybyexample.
var tech = getUrlParameter('technology');
var blog ...
What is the difference between “text” and new String(“text”)?
... String s = "text"; may reuse an instance from the string constant pool if one is available.
You very rarely would ever want to use the new String(anotherString) constructor. From the API:
String(String original) : Initializes a newly created String object so that it represents the same sequenc...
How to get the primary IP address of the local machine on Linux and OS X? [closed]
...f sed from a FreeBSD release of a few years ago. Not sure precisely which one, as OSX has adoped FreeBSD source code a few times over the years. I believe the use of -E was intended to be comparable to grep's -E option. No idea why GNU folks opted for -r instead.
– ghoti
...
Store select query's output in one array in postgres
...
There are two ways. One is to aggregate:
SELECT array_agg(column_name::TEXT)
FROM information.schema.columns
WHERE table_name = 'aean'
The other is to use an array constructor:
SELECT ARRAY(
SELECT column_name
FROM information.schema.column...
How can you represent inheritance in a database?
...table as in your first option is probably the simplest design. As you mentioned, many attributes that are subtype-specific will have to be given a NULL value on rows where these attributes do not apply. With this model, you would have one policies table, which would look something like this:
+------...