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What is the difference between map and flatMap and a good use case for each?
...th N.
For example, it maps from two lines into two line-lengths:
rdd.map(_.length).collect
res1: Array[Int] = Array(13, 16)
But flatMap (loosely speaking) transforms an RDD of length N into a collection of N collections, then flattens these into a single RDD of results.
rdd.flatMap(_.spli...
How do I convert a double into a string in C++?
...
The boost (tm) way:
std::string str = boost::lexical_cast<std::string>(dbl);
The Standard C++ way:
std::ostringstream strs;
strs << dbl;
std::string str = strs.str();
Note: Don't forget #include <sstream>
...
Getting name of windows computer running python script?
...i
win32api.GetComputerName()
>>'MYNAME'
Or:
import win32api
WIN32_ComputerNameDnsHostname = 1
win32api.GetComputerNameEx(WIN32_ComputerNameDnsHostname)
>> u'MYNAME'
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improv...
Split string in Lua?
...%s, like %D is the negation of %d. Additionally, %w is equal to [A-Za-z0-9_] (other characters might be supported depending on your locale).
– Lars Gyrup Brink Nielsen
Jan 2 '14 at 22:00
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Where are shared preferences stored?
...ces are stored in an xml file in the app data folder, i.e.
/data/data/YOUR_PACKAGE_NAME/shared_prefs/YOUR_PREFS_NAME.xml
or the default preferences at:
/data/data/YOUR_PACKAGE_NAME/shared_prefs/YOUR_PACKAGE_NAME_preferences.xml
SharedPreferences added during runtime are not stored in the Eclip...
Create space at the beginning of a UITextField
...tField in your app:
extension UITextField {
func setLeftPaddingPoints(_ amount:CGFloat){
let paddingView = UIView(frame: CGRect(x: 0, y: 0, width: amount, height: self.frame.size.height))
self.leftView = paddingView
self.leftViewMode = .always
}
func setRightPadd...
Importing variables from another file?
...
Did you have a __init__.py file? See here for more details.
– J0ANMM
Sep 28 '16 at 7:21
...
Convert interface{} to int
...)
}
func addTwoNumbers(val1 interface{}, val2 interface{}) int {
op1, _ := val1.(int)
op2, _ := val2.(int)
return op1 + op2
}
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What JSON library to use in Scala? [closed]
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+1 for "net.liftweb" % "lift-json_2.10" % "2.5.1"
– Dylan Hogg
Jun 5 '14 at 6:00
2
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Delete/Reset all entries in Core Data?
...NSEntityDescription entityForName:entityDescription inManagedObjectContext:_managedObjectContext];
[fetchRequest setEntity:entity];
NSError *error;
NSArray *items = [_managedObjectContext executeFetchRequest:fetchRequest error:&error];
[fetchRequest release];
for (NSManage...