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Difference between classification and clustering in data mining? [closed]
Can someone explain what the difference is between classification and clustering in data mining?
21 Answers
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Remove Identity from a column in a table
...e (nearly 500 million rows) and we want to remove the identity property on one of the column, but when we try to do this through SSMS - it times out.
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Is log(n!) = Θ(n·log(n))?
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@Keith: I don't get it yet. Could you (or someone) expand a few more terms for me in the "..." part of "log(n/2) + ... + log(n)" please? Thanks!
– j_random_hacker
Jan 21 '10 at 9:31
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Is a view faster than a simple query?
...ting queries.
Update: At least three people have voted me down on this one. With all due respect, I think that they are just wrong; Microsoft's own documentation makes it very clear that Views can improve performance.
First, simple views are expanded in place and so do not directly contribute t...
LINUX: Link all files from one to another directory [closed]
...1 -print "%P\n" | while read file; do ln -s "/mnt/usr/lib/$file" "$file"; done
If you should happen to want to recursively create the directories and only link files (so that if you create a file within a directory, it really is in /usr/lib not /mnt/usr/lib), you could do this:
cd /usr/lib
find /...
How to move up a directory with Terminal in OS X
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cd .. will back the directory up by one. If you want to reach a folder in the parent directory, you can do something like cd ../foldername. You can use the ".." trick as many times as you want to back up through multiple parent directories. For example, cd ../....
Getting all names in an enum as a String[]
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Here's one-liner for any enum class:
public static String[] getNames(Class<? extends Enum<?>> e) {
return Arrays.stream(e.getEnumConstants()).map(Enum::name).toArray(String[]::new);
}
Pre Java 8 is still a one-lin...
What is the use of printStackTrace() method in Java?
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This is normal, with the 1st one you call the toString() of the error, and in the 2nd you ask to print all the stackTrace from the error. That's 2 différents things.
– Jon
May 17 '16 at 8:08
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How to represent multiple conditions in a shell if statement?
...g; c = $c; true"
else echo "g = $g; c = $c; false"
fi
done
done
Example run, using Bash 3.2.57 on Mac OS X:
g = 1; c = 123; true
g = 1; c = 456; false
g = 1; c = 789; false
g = 2; c = 123; false
g = 2; c = 456; true
g = 2; c = 789; false
g = 3; c = 123; false
g = 3; c = 456; f...
don't fail jenkins build if execute shell fails
...answered Sep 9 '14 at 13:13
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