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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
I'm having a little trouble understanding the pass-by-reference properties of data.table . Some operations seem to 'break' the reference, and I'd like to understand exactly what's happening.
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How to write asynchronous functions for Node.js
I've tried to research on how exactly asynchronous functions should be written. After a lot of plowing through a lot of documentation, it's still unclear to me.
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How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
What is the difference between == and === in PHP?
11 Answers
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Is it safe to check floating point values for equality to 0?
I know you can't rely on equality between double or decimal type values normally, but I'm wondering if 0 is a special case.
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Best way to test if a row exists in a MySQL table
I'm trying to find out if a row exists in a table. Using MySQL, is it better to do a query like this:
12 Answers
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Replacing NAs with latest non-NA value
In a data.frame (or data.table), I would like to "fill forward" NAs with the closest previous non-NA value. A simple example, using vectors (instead of a data.frame ) is the following:
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Drawing an image from a data URL to a canvas
How can i open an image in a Canvas ? which is encoded
6 Answers
6
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Change the Right Margin of a View Programmatically?
Can this attribute be changed dynamically in Java code?
4 Answers
4
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How can I get a list of locally installed Python modules?
I would like to get a list of Python modules, which are in my Python installation (UNIX server).
30 Answers
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How to convert a boolean array to an int array
I use Scilab, and want to convert an array of booleans into an array of integers:
6 Answers
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