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What is the difference between “INNER JOIN” and “OUTER JOIN”?
... and the query returns the single red row not matched in table B. This is known as an anti semi join.
It is important to select a column for the IS NULL test that is either not nullable or for which the join condition ensures that any NULL values will be excluded in order for this pattern to work co...
How to set or change the default Java (JDK) version on OS X?
...the major version, like:
export JAVA_HOME=`/usr/libexec/java_home -v 1.8`
Now when you run java -version you will see:
java version "1.6.0_65"
Java(TM) SE Runtime Environment (build 1.6.0_65-b14-462-11M4609)
Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-462, mixed mode)
Add the export JAVA_HO...
getActionBar() returns null
...ionBar() instead of getActionBar()
* Update:
The class ActionBarActivity now is deprecated:
import android.support.v7.app.ActionBarActivity;
I recommend to use:
import android.support.v7.app.AppCompatActivity
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How can I check if a checkbox is checked?
... didn't check it! Let me check it for you.");
}
}
Your script doesn't know what the variable remember is. You need to get the element first using getElementById().
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np.mean() vs np.average() in Python NumPy?
... already noted, there's another extremely important difference that I just now discovered the hard way: unlike np.mean, np.average doesn't allow the dtype keyword, which is essential for getting correct results in some cases. I have a very large single-precision array that is accessed from an h5 f...
Infinity symbol with HTML
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Now this is the first page that comes up when you google the question.
– whitebeard
Jul 23 '15 at 11:25
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Inheriting class methods from modules / mixins in Ruby
It is known that in Ruby, class methods get inherited:
4 Answers
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Why do people say there is modulo bias when using a random number generator?
...t defined in cstdlib (see this article for a general overview on rand()).
Now what happens if you want to generate a random number between say 0 and 2? For the sake of explanation, let's say RAND_MAX is 10 and I decide to generate a random number between 0 and 2 by calling rand()%3. However, rand()...
Kill child process when parent process is killed
...nifest once again? Apparently there's a break in the clouds, as Windows 8 now allows a process to belong to multiple jobs. [3] So I haven't tested it yet, but I imagine that this madness will be over now if you simply include a manifest with the supportedOS information.
Tip 1: If you're developing...
c#: getter/setter
...omething like the following somewhere, and was wondering what it meant. I know they are getters and setters, but want to know why the string Type is defined like this. Thanks for helping me.
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