The Adaptive Business Network in Practice in .NET

Generator QRCode in .NET The Adaptive Business Network in Practice

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Source: Aberdeen Group October 17, 2007 A benchmark study by Aberdeen Group, a Harte-Hanks company, co-sponsored by Dundas, iDashboards, Insightformation, Corda, and Actuate.

same weights as with the Black-Scholes, the random walk portion is diversi ed, but the jump portion is not constant:

2.3.6.1 Variations in SWRs In our examples, we have assumed a xed SWR for each module in computing variances. If these are maximum SWRs, the

objects in the original collection also should be in the new collection. To create a collection called tools_articles that is a subset of all elements, where the category is Tools , use: context Order inv: tools_articles = ordered_articles->select(category = 'Tools') The reject operation performs an operation similar to the select operation, with the exception that those objects that match the expression are rejected from the new collection. The forall operation tests an expression on all elements in a collection. In order for the operation to return true, the expression must be true for all elements. The following example of the forall operation also shows that more than one object can be referred to in an expression. It uses two iterators, a1 and a2, that iterate over all the objects in the entire collection. The expression then specifies that if a1 differs from a2, the number attribute must be different for the objects. This is equivalent to specifying that the number attribute must be unique for all Article objects, as shown next: context Article inv: Article.allInstances->forAll(a1, a2 : Article | a1 <> a2 implies a1.number <> a2.number) Another feature for collection is called isUnique. This feature can be used more conveniently to describe the previous constraint: context Article inv: Article.allInstances->isUnique(a : Article | a.number) The exists operation also tests an expression on all objects in a collection, but in order for the operation to return true, only one of the objects has to satisfy the expression. The following expression returns true if at least one article of the category Tools is in stock: context Article inv: Article.allInstances->exists(category = 'Tools' and availability = #inStock) Collection operators never change the contents of a collection, because OCL is free from side effects. They either return a new collection or a specific value, such as a Boolean (true or false).