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How do I parallelize a simple Python loop?
... output3.append(out3)
finish = time.time()
# these kinds of format strings are only available on Python 3.6:
# time to upgrade!
print(f'original inputs: {repr(output1)}')
print(f'total time to execute {sum(output2)} = sum({repr(output2)})')
print(f'time saved by parallelizing...
How to check iOS version?
...if UIPopoverController is available on the current device using NSClassFromString:
if (NSClassFromString(@"UIPopoverController")) {
// Do something
}
For weakly linked classes, it is safe to message the class, directly. Notably, this works for frameworks that aren't explicitly linked as "Requ...
Is it safe to push_back an element from the same vector?
... a copy of t. Requires: T shall be CopyInsertable into X. Container basic_string, deque, list, vector
So even though it's not exactly trivial, the implementation must guarantee it will not invalidate the reference when doing the push_back.
...
Unable to simultaneously satisfy constraints, will attempt to recover by breaking constraint
...T:
extension NSLayoutConstraint {
override public var description: String {
let id = identifier ?? ""
return "id: \(id), constant: \(constant)" //you may print whatever you want here
}
}
OBJECTIVE-C
@interface NSLayoutConstraint (Description)
@end
@implementation NSL...
Virtual member call in a constructor
...tual void DoSomething()
{
}
}
class Child : Parent
{
private string foo;
public Child()
{
foo = "HELLO";
}
protected override void DoSomething()
{
Console.WriteLine(foo.ToLower()); //NullReferenceException!?!
}
}
The answer is that in fact...
namespaces for enum types - best practices
...default for newly-created enums,
add further methods, like for returning a string representation of a choice.
Just note that you need to declare operator enum_type() so that C++ would know how to convert your class into underlying enum. Otherwise, you won't be able to pass the type to a switch sta...
How to find an element by matching exact text of the element in Capybara
...
Use a regexp instead of a string for the value of the :text key:
find("a", :text => /\ABerlin\z/)
Check out the 'Options Hash' section of the Method: Capybara::Node::Finders#all documentation.
PS: text matches are case sensitive. Your example c...
Angular ng-repeat Error “Duplicates in a repeater are not allowed.”
... however, make sure to look for the difference between JSON.parse and JSON.stringify unless you already know.
– usefulBee
Sep 2 '15 at 14:19
2
...
Java: What is the difference between and ?
...low code to see it in debug.
public class ByteCodeParent
{
public static String name="ByteCode";
public ByteCodeParent()
{
System.out.println("In Constructor");
}
static
{
System.out.println("In Static");
}
{
System.out.println("In Instance");
}
To test, use
Class<B...
C# HttpWebRequest vs WebRequest
... The first would be something like public new static HttpWebRequest Create(string url). Either way, if the url wasn't HTTP(s), it should just throw some InvalidArgumentException.
– Matthew Flaschen
May 22 '09 at 6:06
...