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Best way to check if UITableViewCell is completely visible
I have a UITableView with cells of different heights and I need to know when they are completely visible or not.
10 Answe...
How do I exchange keys with values in a dictionary?
...eyer: agree, also, he's using itertools which are a lot better for big datasets. although i wonder if the final dict() call is also streaming, or if it first assembles the whole pairs list
– Javier
Jul 7 '09 at 19:26
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In which order should floats be added to get the most precise result?
... add the two numbers with the lowest magnitude and reinsert the sum in the set. (Well, probably a merge sort would work best here. You could use the portion of the array containing the previously summed numbers as a working area for the partial sums.)
– Neil
Ju...
How to make an enum conform to a protocol in Swift?
Swift documentation says that classes , structs , and enums can all conform to protocols, and I can get to a point where they all conform. But I can't get the enum to behave quite like the class and struct examples:
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Get all table names of a particular database by SQL query?
I am working on application which can deal with multiple database servers like "MySQL" and "MS SQL Server".
19 Answers
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how to return index of a sorted list? [duplicate]
I need to sort a list and then return a list with the index of the sorted items in the list. For example, if the list I want to sort is [2,3,1,4,5] , I need [2,0,1,3,4] to be returned.
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MVVM in WPF - How to alert ViewModel of changes in Model… or should I?
...s model
Viewmodel subscribes to model's PropertyChanged event
Viewmodel is set as view's DataContext, properties are bound etc
View triggers action on viewmodel
Viewmodel calls method on model
Model updates itself
Viewmodel handles model's PropertyChanged and raises its own PropertyChanged in respon...
How do I get the object if it exists, or None if it does not exist?
... python is to wrap it in a try catch:
try:
go = SomeModel.objects.get(foo='bar')
except SomeModel.DoesNotExist:
go = None
What I did do, is to subclass models.Manager, create a safe_get like the code above and use that manager for my models. That way you can write: SomeModel.objects.safe_...
How to see full query from SHOW PROCESSLIST
When I issue SHOW PROCESSLIST query, only first 100 characters of the running SQL query are returned in the info column.
5 ...
RESTful way to create multiple items in one request
... If the POST request succeeds in its entirety the user is presented with a set of forms for each image resource representation created that allows them to specify more details about each (name, description, etc).
In the event that one or more resources fails to be created, the POST handler aborts a...