Here's a problem I've been trying to solve at work. I'm not a database expert, so that perhaps this is a bit sophomoric. All apologies. I have a given database D, which has been duplicated on another machine (in a perhaps dubious manner), resulting in database D'. It is my task to check that database D and D' are in fact exactly iden...
We are looking to do some heavy security requirements on our project, and we need to do a lot of encryption that is highly performant. I think that I know that PKI is much slower and more complex than symmetric encrpyption, but I can't find the numbers to back up my feelings. ...
Should an API provide Rect::contains(Point) or Point::is_inside(Rect) or both? or Math::contains(Point, Rect) cause it's symmetric? The same Q goes for LineSegment::contains(Point), Rect::fully_contains(Circle) etc. ...
Client has an simple increasing order number (1, 2, 3...). He wants end-users to receive an 8- or 9- digit (digits only -- no characters) "random" number. Obviously, this "random" number actually has to be unique and reversible (it's really an encryption of the actualOrderNumber). My first thought was to just shuffle some bits. When I ...
Hello, I am learning C++ and I was wondering if I could gain some insight into the preferred way of creating binary operators that work on instances of two different types. Here is an example that I've made to illustrate my concerns: class A; class B; class A { private: int x; public: A(int x); int getX() con...
I have to simulate family tree in prolog. And i have problem of symetrical predicates. Facts: parent(x,y). male(x). female(y). age(x, number). Rules: blood_relation is giving me headache. this is what i have done: blood_relation(X,Y):-ancestor(X,Y). blood_relation(X,Y):-uncle(X,Y);brother(X,Y);sister(X,Y);(mother(Z,Y),sister(X,Z));...
I am developing a client server app that uses ssl (openssl) to establish a secure communication channel between the client and the server. I believe I have two options now for secure data transfer between the client and the server. One option is to continue with the data transfer on the established secure ssl channel between the client a...
Is there a way to test wether an arbitrary list is symmetric? For example: ?- symmetric([a,b,b,a]). true. ?- symmetric([a,b,c,a]). false. ?- symmetric([a,a]). true. My attemp was to compare the first element to the last element and if they are equal to remove them and proceed with the rest of the list; otherwise fail. Succeed if th...
The title more or less says it all: I have a function which takes symmetric input in two arguments, e.g. something like def f(a1, a2): return heavy_stuff(abs(a1 - a2)) Now, I want to introduce some caching method. Would it be correct / pythonic / reasonably efficient to do something like this: cache = {} def g(a1, a2): fs =f...
I have a problem similar to the stackoverflow question posed in the link below except that I need to exclude certain fields from the comparison but still include it in the result set. I'm penning the problem as locally symmetric difference. For example Table A and B has columns X,Y,Z and I want to compare only Y,Z for differences but...