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Select rows of a matrix that meet a condition
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This is easier to do if you convert your matrix to a data frame using as.data.frame(). In that case the previous answers (using subset or m$three) will work, otherwise they will not.
To perform the operation on a matrix, you can define a column...
How can I export the schema of a database in PostgreSQL?
... a Windows machine but I'm pretty sure from memory that's the command. See if the help works for you too.
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How to iterate over the files of a certain directory, in Java? [duplicate]
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If you have the directory name in myDirectoryPath,
import java.io.File;
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File dir = new File(myDirectoryPath);
File[] directoryListing = dir.listFiles();
if (directoryListing != null) {
for (File child : directo...
Where does Android emulator store SQLite database?
...best off using adb from the command line to jack into a running emulator. If you can get the specific directory and filename, you can do an "adb pull" to get the database file off of the emulator and onto your regular hard drive.
Edit: Removed suggestion that this works for unrooted devices too - ...
AsyncTask and error handling on Android
...s in the main UI thread. What's unclear to me is how to handle exceptions if something goes haywire in AsyncTask#doInBackground .
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HTML5 dragleave fired when hovering a child element
...ass('red');
},
dragleave: function() {
counter--;
if (counter === 0) {
$(this).removeClass('red');
}
}
});
Note: In the drop event, reset counter to zero, and clear the added class.
You can run it here
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Is there a better way to run a command N times in bash?
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If you have LOTS of iterations, the form with for (n=0;n<k;n++)) may be better; I suspect {1..k} will materialize a string with all those integers separated by spaces.
– Joe Koberg
Se...
How to convert URL parameters to a JavaScript object?
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better if you use JSON.parse('{"' + decodeURI(location.search.substring(1).replace(/&/g, "\",\"").replace(/=/g, "\":\"")) + '"}')
– Daniël Tulp
Apr 3 '13 at 12:06
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Store output of subprocess.Popen call in a string
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if you want to get error stream add stderr: p = subprocess.Popen(["ntpq", "-p"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
– Timofey
May 27 '14 at 12:29
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node.js, socket.io with SSL
I'm trying to get socket.io running with my SSL certificate however, it will not connect.
9 Answers
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