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How to pass a user defined argument in scrapy spider
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The above code is only partially working for me. For eg. If I define domain using self.domain, I'm still not able to access it outside the __init__ method. Python throws a not defined error. BTW, why have you omitted the super call? PS. I'm working wit...
Python string.join(list) on object array rather than string array
...riments says that the list comprehension one can be a good 60% faster on small lists (experiment run 10^6 times on a list of three object()s). However, their performance is similar on big lists (2nd experiment run once on a 10^7 objects() list).
– gozzilli
Mar ...
Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...t is both commutative and associative. This means the operation can be parallelized.
This distinction is very important for Big Data / MPP / distributed computing, and the entire reason why reduce even exists. The collection can be chopped up and the reduce can operate on each chunk, then the red...
Clean code to printf size_t in C++ (or: Nearest equivalent of C99's %z in C++)
...isual C++ for instance use %Iu and %Id respectively, I think that gcc will allow you to use %zu and %zd.
You could create a macro:
#if defined(_MSC_VER) || defined(__MINGW32__) //__MINGW32__ should goes before __GNUC__
#define JL_SIZE_T_SPECIFIER "%Iu"
#define JL_SSIZE_T_SPECIFIER "%Id"
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How do you delete an ActiveRecord object?
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It's destroy and destroy_all methods, like
user.destroy
User.find(15).destroy
User.destroy(15)
User.where(age: 20).destroy_all
User.destroy_all(age: 20)
Alternatively you can use delete and delete_all which won't enforce :before_destroy and :after...
How to do a less than or equal to filter in Django queryset?
I am attempting to filter users by a custom field in each users profile called profile. This field is called level and is an integer between 0-3.
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Passing argument to alias in bash [duplicate]
...etom: If you're referring to the colors in my answer, that's done automatically by the syntax highlighter.
– Paused until further notice.
Jul 7 '14 at 5:12
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What does [:] mean?
...he type of population. If population is a list, this line will create a shallow copy of the list. For an object of type tuple or a str, it will do nothing (the line will do the same without [:]), and for a (say) NumPy array, it will create a new view to the same data.
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Python: Tuples/dictionaries as keys, select, sort
...es and so on.
I'd like to organize them in a data structure in Python that allows for easy selection and sorting. My idea was to put them into a dictionary with tuples as keys, e.g.,
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How do you get a query string on Flask?
...ut since this answer correctly answers the question my Google search terms alluded to ('flask get request parameter') I'm up-voting it anyhow. I'm a pedant too, but I'm chalking this up to web mysticism. ????
– Michael Scheper
Jan 13 '17 at 23:45
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