standards

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 4 years ago . I'm starting a project, willing to use Struts2 and Hibernate. Should I use the struts2-full-hibernate plugin , or integrate them differently ? Searching on Internet confused me: is it the standard way to integrate them ? If not, which is the standard way ? 回答1: In a nutshell:

问题 Hye guys, I included a screenshot to help clarify my problem: http://i40.tinypic.com/mcrnmv.jpg. I'm trying to calculate some kind of moving average and moving standard deviation. The thing is I want to calculate the coefficients of variation (stdev/avg) for the actual value. Normally this is done by calculating the stdev and avg for the past 5 years. However sometimes there will be observations in my database for which I do not have the information of the past 5 years (maybe only 3, 2 etc).

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 5 years ago . Is there a description of Prolog language (syntax and semantics) available online? There are a lot of reference manuals for implementations. But neither of those is a language description. For example the SWI Prolog manual states This manual does not describe the full syntax and semantics of Prolog. And refers

问题 Does anyone know why std::queue, std::stack, and std::priority_queue don't provide a clear() member function? I have to fake one like this: std::queue<int> q; // time passes... q = std::queue<int>(); // equivalent to clear() IIRC, clear() is provided by everything that could serve as the underlying container. Is there a good reason to not have the container adaptors provide it? 回答1: Well, I think this is because clear was not considered a valid operation on a queue, a priority_queue or a

问题 Is it legal to zero array of doubles (using memset(,0,)) or struct containing doubles ? The question implies two different things: (1) From the point of view of C standard, is this UB of not ? (on a fixed platform, how can this UB ... it just depends of floating representation that's all ...) (2) From practical point of view: is it ok on intel platform ? (no matter what standard is saying). 回答1: The C99 standard Annex F says: This annex specifies C language support for the IEC 60559 floating

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 8 years ago . In C99 this was legal: void f(size_t sz) { char arr[sz]; // ... } However, this - dynamically sized stack arrays - has been dropped in

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 8 years ago . As a contrast to this wiki, I am looking for the proper way to implement Swing GUI controls from a coding standpoint. I have been on a quest to learn Java and its GUI tools but I find internet tutorial after internet tutorial that throws everything in main and I know this isn't right. I've also tried RAD systems

问题 This question on 'How to tell if a PHP array is empty' had me thinking of this question Is there a reason that count should be used instead of empty when determining if an array is empty or not? My personal thought would be if the 2 are equivalent for the case of empty arrays you should use empty because it gives a boolean answer to a boolean question. From the question linked above, it seems that count($var) == 0 is the popular method. To me, while technically correct, makes no sense. E.g. Q

问题 The C standard states: ISO/IEC 9899:1999, 6.2.5.15 (p. 49) The three types char, signed char, and unsigned char are collectively called the character types. The implementation shall define char to have the same range, representation, and behavior as either signed char or unsigned char. And indeed gcc define that according to target platform. My question is, why does the standard do that? I can see nothing that can come out of ambiguous type definition, except of hideous and hard to spot bugs.

问题 I just came across a SQL statement that uses AS to alias tables, like this: SELECT all, my, stuff FROM someTableName AS a INNER JOIN someOtherTableName AS b ON a.id = b.id What I'm used to seeing is: SELECT all, my, stuff FROM someTableName a INNER JOIN someOtherTableName b ON a.id = b.id I'm assuming there's no difference and it's just syntactic sugar, but which of these is more prevalent/wide-spread? Is there any reason to prefer one over the other? Edited to clarify: I appreciate all the