initialization

问题 I get this error when i try to compile my code: non-static reference member ‘Timestep& Timestep::previousTimestep’, can’t use default assignment operator I create one Problem which creates a Timestep a reference to the this Timestep should be stored in the vector solution . Besides i want to store a reference to a previous Timestep - and for the first Timestep that would be a reference to itself... I read that i need to define an own operator if i have const members in a class what i try to

问题 I get this error when i try to compile my code: non-static reference member ‘Timestep& Timestep::previousTimestep’, can’t use default assignment operator I create one Problem which creates a Timestep a reference to the this Timestep should be stored in the vector solution . Besides i want to store a reference to a previous Timestep - and for the first Timestep that would be a reference to itself... I read that i need to define an own operator if i have const members in a class what i try to

问题 I read that the constructor is like the first argument passed to the class, which makes sense to me since the parameters seem to be passed to the class via the __init__ method. For example, class NewsStory(object): def __init__(self, guid, title, subject, summary, link): self.guid = guid self.title = title self.subject = subject self.summary = summary self.link = link def get_guid(self): return self.guid def get_title(self): return self.title def get_subject(self): return self.subject def get

问题 I read that the constructor is like the first argument passed to the class, which makes sense to me since the parameters seem to be passed to the class via the __init__ method. For example, class NewsStory(object): def __init__(self, guid, title, subject, summary, link): self.guid = guid self.title = title self.subject = subject self.summary = summary self.link = link def get_guid(self): return self.guid def get_title(self): return self.title def get_subject(self): return self.subject def get

问题 I would like to create instances of a class containing a list that's empty by default; instead of later setting this list to the final full list I would like to successively add items to it. Here's a piece of sample code illustrating this: #!/usr/bin/python class test: def __init__(self, lst=[], intg=0): self.lista = lst self.integer = intg name_dict = {} counter = 0 for name in ('Anne', 'Leo', 'Suzy'): counter += 1 name_dict[name] = test() name_dict[name].integer += 1 name_dict[name].lista

问题 I need to be able to initialize a 2D vector of int's in the same line in which I create it. To be more specific, I have to create a 3x2 size 2D vector and set all of it's values to 0 using only 1 line of code . Is there a way this can be done without using a for loop and several lines of code? 回答1: Try this: std::vector<std::vector<int>> twoDimVector(3, std::vector<int>(2, 0)); 回答2: If you have small 2d vectors (like as you suggested) it can be achieved (using brace-init) quity easily.

问题 I need to be able to initialize a 2D vector of int's in the same line in which I create it. To be more specific, I have to create a 3x2 size 2D vector and set all of it's values to 0 using only 1 line of code . Is there a way this can be done without using a for loop and several lines of code? 回答1: Try this: std::vector<std::vector<int>> twoDimVector(3, std::vector<int>(2, 0)); 回答2: If you have small 2d vectors (like as you suggested) it can be achieved (using brace-init) quity easily.

问题 The initialization process of a group of classes that share a common parent can be divided into three parts: Common initialization Subclass-specific initialization Common post-initialization Currently the first two parts are called from the __init__ method of each child class, but the final post-initialization part has to be called separately, for example class BaseClass: def __init__(self): print 'base __init__' self.common1() def common1(self): print 'common 1' def finalizeInitialization

问题 The initialization process of a group of classes that share a common parent can be divided into three parts: Common initialization Subclass-specific initialization Common post-initialization Currently the first two parts are called from the __init__ method of each child class, but the final post-initialization part has to be called separately, for example class BaseClass: def __init__(self): print 'base __init__' self.common1() def common1(self): print 'common 1' def finalizeInitialization

问题 The initialization process of a group of classes that share a common parent can be divided into three parts: Common initialization Subclass-specific initialization Common post-initialization Currently the first two parts are called from the __init__ method of each child class, but the final post-initialization part has to be called separately, for example class BaseClass: def __init__(self): print 'base __init__' self.common1() def common1(self): print 'common 1' def finalizeInitialization