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Generator Expressions vs. List Comprehension
When should you use generator expressions and when should you use list comprehensions in Python?
9 Answers
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Python Sets vs Lists
...cture is more efficient/speedy? Assuming that order is not important to me and I would be checking for duplicates anyway, is a Python set slower than a Python list?
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How to run functions in parallel?
I researched first and couldn't find an answer to my question. I am trying to run multiple functions in parallel in Python.
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#ifdef replacement in the Swift language
...ifferent value when in Debug or when in Release.
I tested it in real code and it works; it doesn't seem to be recognized in a playground though.
You can read my original post here.
IMPORTANT NOTE: -DDEBUG=1 doesn't work. Only -D DEBUG works. Seems compiler is ignoring a flag with a specific val...
Use of class definitions inside a method in Java
...a local class.
2 is the easy one: yes, a class file will be generated.
1 and 3 are kind of the same question. You would use a local class where you never need to instantiate one or know about implementation details anywhere but in one method.
A typical use would be to create a throw-away impleme...
Run R script from command line
...te that when using R CMD BATCH a.R that instead of redirecting output to standard out and displaying on the terminal a new file called a.Rout will be created.
R CMD BATCH a.R
# Check the output
cat a.Rout
One other thing to note about using Rscript is that it doesn't load the methods package by d...
Load a UIView from nib in Swift
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Original Solution
I created a XIB and a class named SomeView (used the same name for
convenience and readability). I based both on a UIView.
In the XIB, I changed the "File's Owner" class to SomeView (in the identity inspector).
I created a UIView outlet in S...
The difference between the 'Local System' account and the 'Network Service' account?
...the COM object. The error returned from the COM object creation is not a standard COM error (I think it's specific to the COM object being created).
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PHP: exceptions vs errors?
...ere in the PHP manual, but what exactly is the difference between an error and an exception? The only difference that I can see is that errors and exceptions are handled differently. But what causes an exception and what causes an error?
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Fetch the row which has the Max value for a column
...rock"
Edit: With regard to the first comment ...
"using analytic queries and a self-join defeats the purpose of analytic queries"
There is no self-join in this code. There is instead a predicate placed on the result of the inline view that contains the analytic function -- a very different matter...