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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...
Generate MD5 hash string with T-SQL
...here a way to generate MD5 Hash string of type varchar(32) without using fn_varbintohexstr
9 Answers
...
C++ Convert string (or char*) to wstring (or wchar_t*)
...t;locale>
#include <codecvt>
#include <string>
std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> converter;
std::string narrow = converter.to_bytes(wide_utf16_source_string);
std::wstring wide = converter.from_bytes(narrow_utf8_source_string);
Longer online compila...
How does “cat
...rmat to provide a string into stdin. See https://en.wikipedia.org/wiki/Here_document#Unix_shells for more details.
From man bash:
Here Documents
This type of redirection instructs the shell to read input from
the current source until a line
containing only word (with no trailing
bl...
Programmatically Determine a Duration of a Locked Workstation?
...SessionSwitch += new Microsoft.Win32.SessionSwitchEventHandler(SystemEvents_SessionSwitch);
void SystemEvents_SessionSwitch(object sender, Microsoft.Win32.SessionSwitchEventArgs e)
{
if (e.Reason == SessionSwitchReason.SessionLock)
{
//I left my desk
}
else if (e.Reason == ...
Can I incorporate both SignalR and a RESTful API?
...: HubController<ToDoListHub>
{
private static List<string> _items = new List<string>();
public IEnumerable<string> Get()
{
return _items;
}
public void Post([FromBody]string item)
{
_items.Add(item);
// Call add on SignalR cli...
NSRange to Range
...nd 2, so depending on which Swift you're using:
Swift 3.0
func textField(_ textField: UITextField,
shouldChangeCharactersIn range: NSRange,
replacementString string: String) -> Bool {
let nsString = textField.text as NSString?
let newString = nsString?.replaci...
Copying text with color from Notepad++
...eleases you can find the NppExport plugin here: https://github.com/chcg/NPP_ExportPlugin/releases
I've tested "NppExport_0.2.8.16_x64.zip" with Notepad++ v7.5.4.
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Get type of all variables
...te: character
typeof(5 && 4) #doubles are coerced by order of && logical
typeof(8 < 'foobar') #string and double is coerced logical
typeof(list(4, T)[[1]]) #a list retains type at every index: double
typeof(list(4, T)[[2]]) #a list retains type at...
How come a non-const reference cannot bind to a temporary object?
...values to non-const references.
This was a deliberate design decision in order to prevent users from accidentally modifying an object that is going to die at the end of the expression:
g(getx()); // g() would modify an object without anyone being able to observe
If you want to do this, you wil...