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What is the basic difference between the Factory and Abstract Factory Design Patterns? [closed]

... With the Factory pattern, you produce instances of implementations (Apple, Banana, Cherry, etc.) of a particular interface -- say, IFruit. With the Abstract Factory pattern, you provide a way for anyone to provide their own f...
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How to design a database for User Defined Fields?

... If performance is the primary concern, I would go with #6... a table per UDF (really, this is a variant of #2). This answer is specifically tailored to this situation and the description of the data distribution and access patterns described. Pros: Because you indicate tha...
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How to create module-wide variables in Python? [duplicate]

...e a way to set up a global variable inside of a module? When I tried to do it the most obvious way as appears below, the Python interpreter said the variable __DBNAME__ did not exist. ...
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How to duplicate object properties in another object?

...follow | edited Oct 11 '19 at 21:49 Zoltán Matók 3,68122 gold badges2626 silver badges5151 bronze badges ...
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How do I profile memory usage in Python?

I've recently become interested in algorithms and have begun exploring them by writing a naive implementation and then optimizing it in various ways. ...
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how to check if object already exists in a list

... It depends on the needs of the specific situation. For example, the dictionary approach would be quite good assuming: The list is relatively stable (not a lot of inserts/deletions, which dictionaries are not optimized for) T...
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Is there a NumPy function to return the first index of something in an array?

... Yes, here is the answer given a NumPy array, array, and a value, item, to search for: itemindex = numpy.where(array==item) The result is a tuple with first all the row indices, then all the column indices. For example, if an array is two dimensions and it contained your item at two loc...
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Why is 1/1/1970 the “epoch time”?

...ns of unix measured system time in 1/60 s intervals. This meant that a 32-bit unsigned integer could only represent a span of time less than 829 days. For this reason, the time represented by the number 0 (called the epoch) had to be set in the very recent past. As this was in the early 1970s, the e...
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What is a Maven artifact?

What is an artifact and why does Maven need it? 9 Answers 9 ...
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How to get the directory of the currently running file?

... This should do it: import ( "fmt" "log" "os" "path/filepath" ) func main() { dir, err := filepath.Abs(filepath.Dir(os.Args[0])) if err != nil { log.Fatal(err) } fmt.Println(dir) } ...