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How does one reorder columns in a data frame?
... has four columns like so df[,c(1,2,3,4)].
Note the first comma means keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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WebKit issues with event.layerX and event.layerY
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I have disabled all my extensions and I still get these warnings with 1.7.2
– basZero
May 7 '12 at 7:40
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Difference between Activity Context and Application Context
...nformation about the current activity that is necessary to complete those calls. If you show the exact error message, might be able to point to what exactly it needs.
But in general, use the activity context unless you have a good reason not to.
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How to change an application icon programmatically in Android?
...st:
<uses-permission android:name="com.android.launcher.permission.INSTALL_SHORTCUT" />
<uses-permission android:name="com.android.launcher.permission.UNINSTALL_SHORTCUT" />
Then you need this two methods for installing and uninstalling shortcuts. The shortcutAdd method creates a bitm...
How to make links in a TextView clickable?
...ot
// respond to user input. To make them active, you need to
// call setMovementMethod() on the TextView object.
TextView t2 = (TextView) findViewById(R.id.text2);
t2.setMovementMethod(LinkMovementMethod.getInstance());
I removed most of the attributes on my TextView to match wh...
Getting an element from a Set
...as already been added to the Set? For example, when .equals() does not use all of the fields, as the OP specified. A less efficient solution would be to remove the element and re-add it with its values updated.
– KyleM
Feb 19 '13 at 17:48
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Spark java.lang.OutOfMemoryError: Java heap space
... longer need to play with these values, spark will determine them automatically.
Similar to above but shuffle memory fraction. If your job doesn't need much shuffle memory then set it to a lower value (this might cause your shuffles to spill to disk which can have catastrophic impact on speed). So...
How to remove a TFS Workspace Mapping?
...stating "Show Remote Workspaces" - just tick that and you'll get a list of all your enlistments:
From the command line
Call "tf workspace" from a developer command prompt. It will bring up the "Manage Workspaces" directly!
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Add file extension to files with bash
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second one adds an extension on all files, not just extensionless ones
– Jeff
Mar 24 '15 at 15:55
5
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How is set() implemented?
...ts in python have O(1) membership-checking. How are they implemented internally to allow this? What sort of data structure does it use? What other implications does that implementation have?
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