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Trimming a huge (3.5 GB) csv file to read into R
... expert at this, but you might consider trying MapReduce, which would basically mean taking a "divide and conquer" approach. R has several options for this, including:
mapReduce (pure R)
RHIPE (which uses Hadoop); see example 6.2.2 in the documentation for an example of subsetting files
Alterna...
Why does UITableViewCell remain highlighted?
...rs.com/showthread.php?t=577677
Swift version
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
// deselect the selected row if any
let selectedRow: IndexPath? = tableView.indexPathForSelectedRow
if let selectedRowNotNill = selectedRow {
tableVie...
android get all contacts
How can I get all the names of the contacts in my Android and put them into array of strings?
8 Answers
...
Is there a standard sign function (signum, sgn) in C/C++?
...T val) {
return (T(0) < val) - (val < T(0));
}
Benefits:
Actually implements signum (-1, 0, or 1). Implementations here using copysign only return -1 or 1, which is not signum. Also, some implementations here are returning a float (or T) rather than an int, which seems wasteful.
Works ...
Detect if Visual C++ Redistributable for Visual Studio 2012 is installed
How to detect if Visual C++ Redistributable for Visual Studio 2012 is installed?
20 Answers
...
How can I generate Unix timestamps?
... BSD date supports also +%s. Probably universal, as date is normally defined in POSIX.2.
– Dereckson
Nov 5 '17 at 15:41
...
How to get body of a POST in php?
...anual entry on I/O streamsdocs:
php://input is a read-only stream that allows you to read raw data
from the request body. In the case of POST requests, it is preferable
to use php://input instead of $HTTP_RAW_POST_DATA as it does not
depend on special php.ini directives. Moreover, for thos...
How do you specify that a class property is an integer?
... only has the concept of a number, which has a floating point.
Philosophically, the amount of work the compiler would have to do to enforce only whole numbers for a TypeScript int type could potentially be massive and in some cases it would still not be possible to ensure at compile time that only ...
URLs: Dash vs. Underscore [closed]
...
Reasonable guess, but as it turns out, totally untrue. -1.
– Mark Amery
Feb 4 '15 at 23:29
...
check if variable is dataframe
...rame
Yes: isinstance(x, pd.DataFrame)
And don't even think about
if obj.__class__.__name__ = 'DataFrame':
expect_problems_some_day()
isinstance handles inheritance (see What are the differences between type() and isinstance()?). For example, it will tell you if a variable is a string (eithe...