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How to unload a package without restarting R
... (mostly because restarting R as I try out different, conflicting packages is getting frustrating, but conceivably this could be used in a program to use one function and then another--although namespace referencing is probably a better idea for that use).
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How to maintain aspect ratio using HTML IMG tag
... img tag to 64, it's not maintaining the aspect ratio, so the image looks distorted.
9 Answers
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Index of Currently Selected Row in DataGridView
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There is the RowIndex property for the CurrentCell property for the DataGridView.
datagridview.CurrentCell.RowIndex
Handle the SelectionChanged event and find the index of the selected row as above.
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Android Json and null values
How can I detect when a json value is null?
for example: [{"username":null},{"username":"null"}]
6 Answers
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Deleting multiple elements from a list
Is it possible to delete multiple elements from a list at the same time? If I want to delete elements at index 0 and 2, and try something like del somelist[0] , followed by del somelist[2] , the second statement will actually delete somelist[3] .
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JavaScript and Threads
Is there some way to do multi-threading in JavaScript?
13 Answers
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How to center absolute div horizontally using CSS?
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You need to set left: 0 and right: 0.
This specifies how far to offset the margin edges from the sides of the window.
Like 'top', but specifies how far a box's right margin edge is offset to the [left/right] of the [right/left] edge of the box's containing bloc...
Keep SSH session alive [closed]
...ign-of-life signal to the server once in a while.
The configuration for this is in the file $HOME/.ssh/config, create the file if it does not exist (the config file must not be world-readable, so run chmod 600 ~/.ssh/config after creating the file). To send the signal every e.g. four minutes (240 s...
Spring MVC: Complex object as GET @RequestParam
Suppose i have a page that lists the objects on a table and i need to put a form to filter the table. The filter is sent as an Ajax GET to an URL like that: http://foo.com/system/controller/action?page=1&prop1=x&prop2=y&prop3=z
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Generate random numbers using C++11 random library
...mbers using the new C++11 <random> library. I have tried it with this code:
6 Answers
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