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What is the difference between ndarray and array in numpy?
...an array using __new__:
If buffer is None, then only shape, dtype, and order are used.
If buffer is an object exposing the buffer interface, then all keywords are interpreted.
The example below gives a random array because we didn't assign buffer value:
np.ndarray(shape=(2,2), dtype=float...
Composite Key with EF 4.1 Code First
...uld work - composite key defined with annotations requires explicit column order:
public class ActivityType
{
[Key, Column(Order = 0)]
public int ActivityID { get; set; }
[Key, Column(Order = 1)]
[Required(ErrorMessage = "A ActivityName is required")]
[StringLength(50, ErrorMes...
Why is lazy evaluation useful?
...zy language. Strictness also exacerbates the fact that where has no way to order the relative effects at all, except by SCC, it is a statement level construction, its effects could happen in any order strictly, and even if you have a pure language you wind up with the #f issue. Strict where riddles ...
Is using Random and OrderBy a good shuffle algorithm?
...basically giving a random (hopefully unique!) number to each element, then ordering the elements according to that number.
I prefer Durstenfield's variant of the Fisher-Yates shuffle which swaps elements.
Implementing a simple Shuffle extension method would basically consist of calling ToList or T...
How can I select rows with most recent timestamp for each key value?
...SELECT MAX(timestamp) FROM sensorTable s2 WHERE s1.sensorID = s2.sensorID)
ORDER BY sensorID, timestamp;
Pretty self-explaining I think, but here's more info if you wish, as well as other examples. It's from the MySQL manual, but above query works with every RDBMS (implementing the sql'92 standard...
Where should I put tags in HTML markup?
...efer></script>
Scripts with the defer attribute are executed in order (i.e. first script 1, then script 2). This also does not block the browser.
Unlike async scripts, defer scripts are only executed after the entire document has been loaded.
According to http://caniuse.com/#feat=script...
How to attach javadoc or sources to jars in libs folder?
...ers from Xavier, plastiv, VinceFR and Christopher.
Step by step guide
In order to link the sources and javadoc to a .jar library that is automatically linked by Eclipse you have to do the following:
Place the library .jar file in the libs folder, and the associated source .jar and doc .jar files...
Facebook Graph API v2.0+ - /me/friends returns empty, or only friends who also use my application
...efault in every login. Each user must grant the user_friends permission in order to appear in the response to /me/friends. See the Facebook upgrade guide for more detailed information, or review the summary below.
If you want to access a list of non-app-using friends, there are two options:
If yo...
How to sort a list/tuple of lists/tuples by the element at a given index?
...
In order to sort a list of tuples (<word>, <count>), for count in descending order and word in alphabetical order:
data = [
('betty', 1),
('bought', 1),
('a', 1),
('bit', 1),
('of', 1),
('butter', 2),
('but', 1),
('...
Pagination in a REST web application
...ings are not first-class resource identifiers; they just clarification for ordering and grouping of the resource.
– S.Lott
Mar 2 '10 at 21:16
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