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When is del useful in python?
I can't really think of any reason why python needs the del keyword (and most languages seem to not have a similar keyword). For instance, rather than deleting a variable, one could just assign None to it. And when deleting from a dictionary, a del method could be added.
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Type List vs type ArrayList in Java [duplicate]
I understand that with (1), implementations of the List interface can be swapped. It seems that (1) is typically used in an application regardless of need (myself I always use this).
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To find whether a column exists in data frame or not
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Assuming that the name of your data frame is dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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JPA: what is the proper pattern for iterating over large result sets?
...only for Hibernate.
So it seems that using setFirstResult/setMaxResults and manual iteration really is necessary. Here's my solution using JPA:
private List<Model> getAllModelsIterable(int offset, int max)
{
return entityManager.createQuery("from Model m", Model.class).setFirstResult(o...
Why is super.super.method(); not allowed in Java?
I read this question and thought that would easily be solved (not that it isn't solvable without) if one could write:
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What is the C# version of VB.net's InputDialog?
...lt", x_coordinate, y_coordinate);
Only the first argument for prompt is mandatory
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Rails find record with zero has_many records associated [duplicate]
... answered Mar 8 '12 at 6:31
AndrewAndrew
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Java: PrintStream to String?
I have a function that takes an object of a certain type, and a PrintStream to which to print, and outputs a representation of that object. How can I capture this function's output in a String? Specifically, I want to use it as in a toString method.
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How to check for a valid Base64 encoded string
...to see if a string is Base 64 encoded other than just trying to convert it and see if there is an error? I have code code like this:
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Eclipse Build Path Nesting Errors
... the webcontent folder he wants all of our source code under src/main/java and src/main/webapp.
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