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Should I use a data.frame or a matrix?
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Something not mentioned by @Michal is that not only is a matrix smaller than the equivalent data frame, using matrices can make your code far more efficient than using data frames, often considerably so. That is one reason why internally, a lot of R functions will coerce to matrices data th...
What does -fPIC mean when building a shared library?
...es and independence between individual modules, but I'm not sure what it really means. Can you explain?
3 Answers
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Not equal != operator on NULL
...dicates for such situations.
This behavior is not specific to SQL Server. All standards-compliant SQL dialects work the same way.
Note: To compare if your value is not null, you use IS NOT NULL, while to compare with not null value, you use <> 'YOUR_VALUE'. I can't say if my value equals or ...
Is there a float input type in HTML5?
...>
(I'd also set min=0 if it can only be positive)
If you'd prefer to allow any number of decimal places, you can use step="any" (though for currencies, I'd recommend sticking to 0.01). In Chrome & Firefox, the stepper buttons will increment / decrement by 1 when using any. (thanks to Micha...
How does push notification technology work on Android?
...itiated by the Google Play application. That's why Google Play must be installed on the device for making Google Cloud Messaging (GCM) (formerly Android Cloud to Device Messaging Service - C2DM) work.
When this TCP client socket receives some message, the message contains information such as the pa...
CSS selector for first element with class
...lass. One workaround that Lea Verou and I came up with for this (albeit totally independently) is to first apply your desired styles to all your elements with that class:
/*
* Select all .red children of .home, including the first one,
* and give them a border.
*/
.home > .red {
border: ...
HTML table headers always visible at top of window when viewing a large table
...n if its just a question about how to get it working. Ill respond there usually in under a day. Here ill probably respond in just under a year :)
– mkoryak
Oct 4 '16 at 18:21
1
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Stretch and scale a CSS image in the background - with CSS only
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CSS3 has a nice little attribute called background-size:cover.
This scales the image so that the background area is completely covered by the background image while maintaining the aspect ratio. The entire area will be covered. However, part of the image may...
How to exit in Node.js
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Call the global process object's exit method:
process.exit()
From the docs:
process.exit([exitcode])
Ends the process with the specified code. If omitted, exit uses the 'success' code 0.
To exit with a 'failure' code:
proces...
MongoDB vs. Cassandra [closed]
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Totally different, a comment isn't big enough, but ... Cassandra is a linearly scalable (amortized constant time reads & writes) dynamo/google bigtable hybrid that features fast writes regardless of data size. It's feature s...