constraints

Is there a way to define a generic constraint in Java which would be analogous to the following C# generic constratint ? class Class1<I,T> where I : Interface1, Class2 : I I'm trying to do it like this: class Class1<I extends Interface1, T extends I & Class2> But the compiler complains about the "Class2" part: Type parameter cannot be followed by other bounds. The simplest way I can see of resolving the Java code is to make Class2 an interface. You cannot constrain a type parameter to extends more than one class or type parameter. Further, you can't use super here. This code compiles here fine

When I read the book -- Artificial Intelligence (a modern approach), I came across the following sentence describing the method to convert a n-ary Constraint Search Problem to a binary one: Another way to convert an n-ary CSP to a binary one is the dual graph transformation: create a new graph in which there will be one variable for each constraint in the original graph, and one binary constraint for each pair of constraints in the original graph that share variables. For example, if the original graph has variables {X, Y, Z} and constraints ⟨(X, Y, Z), C1⟩ and ⟨(X, Y ), C2⟩ then the dual

I have this relation. And I have to temporarily destroy it just to change the size of "salID" field using SQL command: ALTER TABLE Adressen DROP CONSTRAINT [ChildTableMainTable] How can I recreate the same relation type using SQL commands? If I use the next SQL I get a one to many relation. This is not what I need: ALTER TABLE MainTable ADD CONSTRAINT [ChildTableMainTable] FOREIGN KEY (salID) REFERENCES [ChildTable] (ChildPK); To the best of my knowledge, Access DDL simply does not support the creation of an Access "Relationship" without "Enforce Referential Integrity". CREATE CONSTRAINT will

I am trying to add constraints to a facebook sdk login button. I have the button inside a scroll view and I am trying to add a top constraint to a label that is also in the scroll view. I am able to successfully add the height constraint with no run time errors but the actual constraint does not seem to be applied to the button. @IBOutlet weak var orLbl: UILabel! @IBOutlet weak var scrollView: UIScrollView! override func viewDidLoad() { super.viewDidLoad() var loginFBButton = FBSDKLoginButton() loginFBButton.readPermissions = ["public_profile", "email"] let heightConstraint =

I am having some issues with deleting data using Laravel 5. I seem to be stuck on a 'foreign key constraint', while I don't see why. In my current database model I have a datapoints table, which has a foreign key to the sensors table (datapoints.sensors_id -> sensor.id). The code I am trying: Route::get('/truncateData', function() { DB::table('datapoints')->truncate(); DB::table('sensors')->truncate(); return 'Done...'; }); The result: SQLSTATE[42000]: Syntax error or access violation: 1701 Cannot truncate a table referenced in a foreign key constraint ( alerting . datapoints , CONSTRAINT

I've tried two ways to constrain a generic type parameter to a nullable type, but both seem to have some unexpected problems. First attempt (using T <: AnyRef): scala> def testAnyRefConstraint[T <: AnyRef](option:Option[T]):T = { | //without the cast, fails with compiler error: | // "found: Null(null) required: T" | option getOrElse null.asInstanceOf[T] | } testAnyRefConstraint: [T <: AnyRef](Option[T])T scala> testAnyRefConstraint(Some("")) res0: java.lang.String = scala> testAnyRefConstraint(Some(0)) <console>:16: error: inferred type arguments [Int] do not conform to method

I have done it in Excel but need to run a proper simulation in R. I need to minimize function F(x) ( x is a vector) while having constraints that sum(x)=1 , all values in x are [0,1] and another function G(x) > G_0 . I have tried it with optim and constrOptim . None of them give you this option. The problem you are referring to is (presumably) a non-linear optimization with non-linear constraints. This is one of the most general optimization problems. The package I have used for these purposes is called nloptr : see here . From my experience, it is both versatile and fast. You can specify both

I have a table with a column that contains a few null values. I want to add a NOT NULL constraint on that column without updating the existing nulls to a non-null value. I want to keep the existing null values and check for future rows that they contain a not null value for this column. Is this possible? How? You can add an unvalidated constraint - it will not look at existing rows, but it will be checked for any new or updated rows. ALTER TABLE mytable MODIFY mycolumn NOT NULL NOVALIDATE; Just be aware that you won't be able to update an existing row unless it satisfies the constraint. Also,