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List distinct values in a vector in R
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You can also use the sqldf package in R.
Z <- sqldf('SELECT DISTINCT tablename.columnname FROM tablename ')
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How do I escape a percentage sign in T-SQL?
... '!' (or your character of choice) to the end of the query.
For example:
SELECT *
FROM prices
WHERE discount LIKE '%80!% off%'
ESCAPE '!'
This will make the database treat 80% as an actual part of the string to search for and not 80(wildcard).
MSDN Docs for LIKE
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What is the best workaround for the WCF client `using` block issue?
...e of the channel factory and channel. ExceptionHandlingProxy respects your selections in the Add Service Reference dialog with respect to asynchronous methods and collection types.
Codeplex has a project called Exception Handling WCF Proxy Generator. It basically installs a new custom tool to Visu...
Object-orientation in C
...ject at runtime! You just reassign it a new vtable pointer. You can even selectively change some of the virtual functions while keeping others, creating new hybrid types. Just be careful to create a new vtable instead of modifying the global vtable, otherwise you'll accidentally affect all object...
Detecting when the 'back' button is pressed on a navbar
...navigationItem.leftBarButtonItem = backButton
}
// Then handle the button selection
func goBack() {
// Here we just remove the back button, you could also disabled it or better yet show an activityIndicator
self.navigationItem.leftBarButtonItem = nil
someData.saveInBackground { (success...
Java 7 language features with Android
...using the JDK 7 (well, as this is the only one and as this is the one I've selected I would have been surprised)
Then I installed the latest version of the Android SDK (EDIT: Honeycomb, API13, at the time this post was written). It found my JDK 7 and installed properly. The same for ADT.
But I ...
How is a tag different from a branch in Git? Which should I use, here?
...;" would generate anonymous unnamed branch (so called 'detached HEAD') and select state of tag. Creating a new commit does it on this unnamed branch, and does not change what tag points to.
– Jakub Narębski
Feb 16 '12 at 14:04
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HSL to RGB color conversion
... CSS 3 specification, which reads:
HOW TO RETURN hsl.to.rgb(h, s, l):
SELECT:
l<=0.5: PUT l*(s+1) IN m2
ELSE: PUT l+s-l*s IN m2
PUT l*2-m2 IN m1
PUT hue.to.rgb(m1, m2, h+1/3) IN r
PUT hue.to.rgb(m1, m2, h ) IN g
PUT hue.to.rgb(m1, m2, h-1/3) IN b
RETURN (r, g, ...
No module named MySQLdb
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Luckily, there is a selection of alternatives, many of which use the same API: Python 3 and MySQL
– Anthony Geoghegan
Mar 24 '15 at 10:07
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What is this Javascript “require”?
...th) {
res.send({});
} else {
var query = client.query('SELECT * FROM BEATLES WHERE name =\''+name+'\' LIMIT 1');
var data = {};
query.on('row', function(row) {
data = row;
res.send(data);
});
};
});
app.listen(80, '127.0.0.1');
...