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Nearest neighbors in high-dimensional data?
...
First, the number of features (columns) in a data set is not a factor in selecting a distance metric for use in kNN. There are quite a few published studies directed to precisely this question, and the usual bases for comparison are:
the underlying statistical
distribution of your data;
the rel...
Sequence contains no elements?
...in dc.BlogPosts
where p.BlogPostID == id
select p).Single();
Also; if this is LINQ-to-SQL, then in the current version you get a slightly better behaviour if you use the form:
var id = ID;
BlogPost post = dc.BlogPosts.Single(p => p.BlogPostID == id);
...
No identities were available - administrator request
...uble click) the new provisioning profile.
In your project's build settings select the NEW provisioning profile (it might have the same name as the old one)
In your project's build settings update your code signing identities (all of them) to the new one if there is one. (The old one was probably exp...
Transaction isolation levels relation with locks on table
... writes data and commit/rollback (depending on results). B just executes a SELECT statement to read data. C reads and updates data. All these process work on the same table T.
READ UNCOMMITTED - no lock on the table. You can read data in the table while writing on it. This means A writes data (unc...
Easier way to debug a Windows service
...classes.
The solution I came up with uses the Environment.Interactive the select running mode, as suggested by other answers to this post.
static void Main()
{
ServiceBase[] servicesToRun;
servicesToRun = new ServiceBase[]
{
new MyService()
};
if (Environment.UserInter...
'App not Installed' Error on Android
...earing all of my cached data. Then, finally I realized all I had to do was select both signature versions when building my signed apk.
Before I only had V2 (Full APK Signature) selected, but after selecting V1 Jar Signature as well, I was able to successfully install my signed APK on my 4.4.2 devic...
Could not load file or assembly 'System.Data.SQLite'
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@Raul Vejar: please elaborate on how application pool selection feature of IIS Express solves the 32-bit/64-bit assembly issue. Thanks
– Tim
Aug 5 '14 at 17:00
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Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?
...pdated) values(null, null);
Query OK, 1 row affected (0.06 sec)
mysql> select * from t5;
+----+---------------------+---------------------+
| id | stamp_created | stamp_updated |
+----+---------------------+---------------------+
| 2 | 2009-04-30 09:44:35 | 2009-04-30 09:44:35 |
+...
How to suppress Java warnings for specific directories or files such as generated code
...rce
Announced here: Eclipse 3.8 and 4.2 M6 - New and Noteworthy, called Selectively ignore errors/warnings from source folders. That's also where the screenshot is from. This is the new feature developed on the previously linked Bug 220928.
...
Delete sql rows where IDs do not have a match from another table
...HERE f.id IS NULL
Using NOT EXISTS:
DELETE FROM BLOB
WHERE NOT EXISTS(SELECT NULL
FROM FILES f
WHERE f.id = fileid)
Using NOT IN:
DELETE FROM BLOB
WHERE fileid NOT IN (SELECT f.id
FROM FILES f)
Warning
Whenever possible, per...