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Convert data.frame columns from factors to characters
I have a data frame. Let's call him bob :
18 Answers
18
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How to unit test abstract classes: extend with stubs?
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Write a Mock object and use them just for testing. They usually are very very very minimal (inherit from the abstract class) and not more.Then, in your Unit Test you can call the abstract method you want to test.
You should test abstract class that contain some logic like all other ...
Query to list number of records in each table in a database
... i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN
sys.allocation_units a ON p.partition_id = a.container_id
WHERE
t.NAME NOT LIKE 'dt%' AND
i.OBJECT_ID > 255 AND
i.index_id <= 1
GROUP BY
t.NAME, i.object_id, i.index_id, i.name, p.[Rows]
ORDER BY
o...
Self-references in object literals / initializers
...some kind of one time initialization of the object.
Note that you are actually assigning the return value of init() to foo, therefore you have to return this.
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What unique features does Firebug have that are not built-in to Firefox?
...There are more things missing, which are tracked in a bug report filed for all the gaps between Firebug and the Firefox DevTools.
Firebug integration
Firebug is now built on top of the native developer tools.
Since Firefox 48 there's also a Firebug theme that looks like the Firebug extension, lett...
Javascript switch vs. if…else if…else
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Answering in generalities:
Yes, usually.
See More Info Here
Yes, because each has a different JS processing engine, however, in running a test on the site below, the switch always out performed the if, elseif on a large number of iterations.
Test site
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Order of serialized fields using JSON.NET
...etting the order to 1 will only work if you set an order greater than 1 on all other properties. By default any property without an Order setting will be given an order of -1. So you must either give all serialized properties and order, or set your first item to -2
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Avoid modal dismiss on enter keypress
...d the <a> items, I guess it's something else. The code I use is basically the sample code on the bootstrap page, just with a form added inside
– Luke Morgan
May 2 '12 at 10:54
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CSS – why doesn’t percentage height work? [duplicate]
...s house?</p>
</div>
</div>
#inner will grow to be tall enough to contain the paragraph and #outer will grow to be tall enough to contain #inner.
When you specify the height or width as a percentage, that's a percentage with respect to the element's parent. In the case of wid...
Why use the params keyword?
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With params you can call your method like this:
addTwoEach(1, 2, 3, 4, 5);
Without params, you can’t.
Additionally, you can call the method with an array as a parameter in both cases:
addTwoEach(new int[] { 1, 2, 3, 4, 5 });
That is, par...