implementation

I am a little with familiar with C++ and I know that for almost every header file, I must create source file to go with it. Now I am looking into java interfaces and implementation and it looks as the same thing. At first you just name the variables and methods in one class and then you define them in other class. Are these things in C++ and Java basically the same or similar? Java interfaces and C++ header/implementation files are different concepts. C++ has a text compilation model. So, to use something - such as a function - in your code, the compiler must first have parsed a definition of

I'd need an Erlang implementation of the OpenId protocol. I found the following, but it seems to be a project on its early stage. http://code.google.com/p/erlopenid/ Any hint or suggestion on what should I use? I finally found all the existing Erlang implementations for OpenID thanks to the following search engine for Erlang projects: http://projects.trapexit.org/web/ Here are the results: http://github.com/etnt/eopenid http://github.com/brendonh/erl_openid http://github.com/pib/erlangopenid http://code.google.com/p/erlopenid/ http://code.google.com/p/erlopenid-mochiweb/ 来源： https:/

I have the following situation in my python code: class Parent(object): def run(self): print "preparing for run" self.runImpl() print "run done" class Child(Parent): def runImpl(self): print "child running" However, I have several such 'decorators', doing different setup/teardown steps before and after 'runImpl', and I don't like having to define run() , runImpl() , runImplSingleProcess() etc. I am looking for a solution of the following form: class Parent(object): @wrapping_child_call def run(self, func_impl, *args, **kwargs) print "preparing for run" func_impl(*args, **kwargs) print "run

I get the concept behind a trie . But I get a little confused when it comes to implementation. The most obvious way I could think to structure a Trie type would be to have a Trie maintain an internal Dictionary<char, Trie> . I have in fact written one this way, and it works , but... this seems like overkill. My impression is that a trie should be lightweight, and having a separate Dictionary<char, Trie> for every node does not seem very lightweight to me. Is there a more appropriate way to implement this structure that I'm missing? UPDATE : OK! Based on the very helpful input from Jon and

I have implemented the Kalman Smoothing with Expectation Maximization based on the Paper Parameter Estimation for Linear dynamical system . All notations are based on this paper. The model is an IIR (AR(2)) filter y(t) = 0.195 *y(t-1) - 0.95*y(t-2) + w(t) The state space representation: x(t+1) = a^Tx(t) + w(t) y(t) = C(t) + v(t) The state space model : x(t+1) = Ax(t) + w(t) y(t) = Cx(t) + v(t) w(t) = N(0,Q) is the driving process noise v(t) = N(0,R) is the measurement noise Re-writing the AR model as State Space representation: Can somebody please point out where I have done wrong so that the