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Should an Enum start with a 0 or a 1?
...stic trade off I guess - disk space is cheap though, time spent constantly converting between enum values and an intwhen searching the db is relatively expensive (doubly so if you have a reporting tool setup against a database or something similar). If you're worried abotu space, with the newer SQL ...
Rename Pandas DataFrame Index
...s and index are the same type of object (Index or MultiIndex), and you can interchange the two via transpose.
This is a little bit confusing since the index names have a similar meaning to columns, so here are some more examples:
In [1]: df = pd.DataFrame([[1, 2, 3], [4, 5 ,6]], columns=list('ABC'...
How to Implement Custom Table View Section Headers and Footers with Storyboard
...
@Foriger - Not at this point. It's an odd omission in storyboard table views, but it is what it is. Use that kludgy hack with prototype cells if it you want, but personally, I just put up with the annoyance of the NIBs for the header/footer views.
...
How to repeat a string a variable number of times in C++?
... to repeat a string n times:
#include <sstream>
std::string repeat(int n) {
std::ostringstream os;
for(int i = 0; i < n; i++)
os << "repeat";
return os.str();
}
Depending on the implementation, this may be slightly more efficient than simply concatenating the s...
Paging with Oracle
... stored proc. If I have "Page Number" and "Number of records per page" as integer values I can pass as parameters, what would be the best way to get back just that particular section. Say, if I pass 10 as a page number, and 120 as number of pages, from the select statement it would give me the 188...
How to create index on JSON field in Postgres?
...
Found:
CREATE TABLE publishers(id INT, info JSON);
CREATE INDEX ON publishers((info->>'name'));
As stated in the comments, the subtle difference here is ->> instead of ->. The former one returns the value as text, the latter as a JSON object...
How do you set the text in an NSTextField?
...ng to set happens to be an integer rather than a string, you don't need to convert the integer value to a string manually; you can just call:
myLabel.integerValue = i;
The integerValue property is defined on NSTextField's parent class, NSControl. See that linked documentation page for a full list...
What is “Argument-Dependent Lookup” (aka ADL, or “Koenig Lookup”)?
...void doSomething(MyClass);
}
MyNamespace::MyClass obj; // global object
int main()
{
doSomething(obj); // Works Fine - MyNamespace::doSomething() is called.
}
In the above example there is neither a using-declaration nor a using-directive but still the compiler correctly identifies the unqu...
Why implement interface explicitly?
So, what exactly is a good use case for implementing an interface explicitly?
11 Answers
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Good Hash Function for Strings
...it more likely to generate unique hashes) So you could do something like:
int hash = 7;
for (int i = 0; i < strlen; i++) {
hash = hash*31 + charAt(i);
}
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