大约有 14,000 项符合查询结果（耗时：0.0240秒） [XML]
How does the Amazon Recommendation feature work?
...nearest neighbor methods, and neural networks. Here are some papers by the winning team:
R. Bell, Y. Koren, C. Volinsky, "The BellKor 2008 Solution to the Netflix Prize", (2008).
A. Töscher, M. Jahrer, “The BigChaos Solution to the Netflix Prize 2008", (2008).
A. Töscher, M. Jahrer, R. Legens...
NSObject +load and +initialize - What do they do?
...ories define the same method on the same class, one of the methods will “win” and be used, and the other method will never be called.
The initialize Method
The runtime calls the initialize method on a class object just before sending the first message (other than load or initialize) to the cla...
How to start two threads at “exactly” the same time
...
@Santa - The Win32 API for example offers different primitives. One useful type is the manual reset event returned when you call CreateEvent. msdn.microsoft.com/en-us/library/ms686364%28VS.85%29.aspx
– ChaosPandion
...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
... preferred whenever practical.
In this case, you typically follow the following process:
CREATE a TEMPORARY table
COPY or bulk-insert the new data into the temp table
LOCK the target table IN EXCLUSIVE MODE. This permits other transactions to SELECT, but not make any changes to the table.
Do an ...
How does `is_base_of` work?
How does the following code work?
5 Answers
5
...
How does BLAS get such extreme performance?
...t all).
IMHO no BLAS implementation uses algorithms like the Coppersmith–Winograd algorithm or the Strassen algorithm. The likely reasons are:
Maybe its not possible to provide a cache optimized implementation of these algorithms (i.e. you would loose more then you would win)
These algorithms a...
Performance surprise with “as” and nullable types
.... While the IL code for the new syntax is indeed 1 byte smaller, it mostly wins big by making zero calls (vs. two) and avoiding the unbox operation altogether when possible.
// static void test1(Object o, ref int y)
// {
// int? x = o as int?;
// if (x.HasValue)
// y = x.Value;
// }...
When do you use POST and when do you use GET?
... to provide the PUT and DELETE calls also.
But, even if you are not following RESTful principles, it can be useful to think in terms of using GET for retrieving / viewing information and POST for creating / editing information.
You should never use GET for an operation which alters data. If a se...
Check if at least two out of three booleans are true
...;
Thread.sleep(1000);
}
}
}
This prints the following on my machine (running Ubuntu on Intel Core 2 + sun java 1.6.0_15-b03 with HotSpot Server VM (14.1-b02, mixed mode)):
First and second iterations:
a&&b || b&&c || a&&c : 1740 ms
a ? b||c : b&...
Regular expression that matches valid IPv6 addresses
...}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]))
For ease of reading, the following is the above regular expression split at major OR points into separate lines:
# IPv6 RegEx
(
([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}| # 1:2:3:4:5:6:7:8
([0-9a-fA-F]{1,4}:){1,7}:| # 1:: ...