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What is a “callable”?

...t's clear what a metaclass is , there is an associated concept that I use all the time without knowing what it really means. ...
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Why is it slower to iterate over a small string than a small list?

...nd with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time. ...
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Difference between Role and GrantedAuthority in Spring Security

...thority as being a "permission" or a "right". Those "permissions" are (normally) expressed as strings (with the getAuthority() method). Those strings let you identify the permissions and let your voters decide if they grant access to something. You can grant different GrantedAuthoritys (permissions...
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How do I choose grid and block dimensions for CUDA kernels?

...eads per block should be a round multiple of the warp size, which is 32 on all current hardware. Each streaming multiprocessor unit on the GPU must have enough active warps to sufficiently hide all of the different memory and instruction pipeline latency of the architecture and achieve maximum throu...
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How to pass a user defined argument in scrapy spider

... 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...
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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 ...
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Is there a built-in function to print all the current properties and values of an object?

... You are really mixing together two different things. Use dir(), vars() or the inspect module to get what you are interested in (I use __builtins__ as an example; you can use any object instead). >>> l = dir(__builtins__) &gt...
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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...
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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 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. ...