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Reshaping data.frame from wide to long format
...s melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
...
Can't operator == be applied to generic types in C#?
...ase share.
namespace TestProject
{
class Program
{
static void Main(string[] args)
{
Test a = new Test();
Test b = new Test();
Console.WriteLine("Inline:");
bool x = a == b;
Console.WriteLine("Generic:");
Compare<Test>(a, b);
}
...
Hidden features of mod_rewrite
...REQUEST_FILENAME} !-d
# map requests to index.php and append as a query string
RewriteRule ^(.*)$ index.php?query=$1
Since Apache 2.2.16 you can also use FallbackResource.
Handling 301/302 redirects:
RewriteEngine on
# 302 Temporary Redirect (302 is the default, but can be specified for clari...
Programmatically open Maps app in iOS 6
...ion map item. I haven't tried that.
Finally, if you have an address (as a string) that you want directions to, use the geocoder to create an MKPlacemark, by way of CLPlacemark.
// Check for iOS 6
Class mapItemClass = [MKMapItem class];
if (mapItemClass && [mapItemClass respondsToSelector:@...
PowerMockito mock single static method and return object
....modules.junit4.PowerMockRunner;
class ClassWithStatics {
public static String getString() {
return "String";
}
public static int getInt() {
return 1;
}
}
@RunWith(PowerMockRunner.class)
@PrepareForTest(ClassWithStatics.class)
public class StubJustOneStatic {
@Test
public void...
SQL standard to escape column names?
...
According to SQLite,
'foo' is an SQL string
"foo" is an SQL identifier (column/table/etc)
[foo] is an identifier in MS SQL
`foo` is an identifier in MySQL
For qualified names, the syntax is: "t"."foo" or [t].[foo], etc.
MySQL supports the standard "foo" when ...
How do I add 1 day to an NSDate?
...
@quemeful extension Date { func adding(_ component: Calendar.Component, _ value: Int) -> Date? { return Calendar.current.date(byAdding: component, value: value, to: self) } } usage Date().adding(.day, 1) // "Jun 6, 2019 at 5:35 PM"
...
Inspect attached event handlers for any DOM element
...k= handler or HTML <element onclick="handler"> can be retrieved trivially from the element.onclick property from script or in-debugger.
Event handlers attached using DOM Level 2 Events addEventListener methods and IE's attachEvent cannot currently be retrieved from script at all. DOM Level 3 ...
Core Data: Quickest way to delete all instances of an entity
...
Reset Entity in Swift 3 :
func resetAllRecords(in entity : String) // entity = Your_Entity_Name
{
let context = ( UIApplication.shared.delegate as! AppDelegate ).persistentContainer.viewContext
let deleteFetch = NSFetchRequest<NSFetchRequestResult>(entityNa...
Coding Conventions - Naming Enums
..."coords"), SHAPE("shape"), TARGET_IMAGE("targetImage");
private final String val;
private PropertyKeys(String val) {
this.val = val;
}
@Override
public String toString() {
return val;
}
}
So it seems even the guys at Oracle sometimes trade convention with...