Re: Real_Arrays on heap with overloaded operators and clean syntax

[Jim Paloander <dhmos.altiotis@gmail.com>]

> > Dear ADA lovers, 
> > with stack allocation of Real_Vector ( 1 .. N ) when N >= 100,000 I get STACK_OVERFLOW ERROR while trying to check how fast operator overloading is working for an expression 
> > 
> > X := A + B + C + C + A + B, where 
> > A,B,C,X are all Real_Vector ( 1 .. N ). 
> > 
> > So my only option was to allocate on the heap using new. But then I lost the clean syntax 
> > 
> > X := A + B + C + C + A + B 
> > 
> > and I had to write instead: 
> > 
> > X.all := A.all + B.all + C.all + C.all + A.all + B.all. 
> > 
> > This is really ugly and annoying because when you are using Real_Arrays for implementing some linear algebra method who relies heavilly on matrix vector products and vector updates, you do need to allocate on the heap (sizes are determined in runtime) and you do need a clean syntax. So, is there any way to simplify my life without using the .all or even without declaring A,B,C,X as access Real_Vector? 
> > Thanks for your time!
> Easiest solution is probably to declare a new task and specify the stack size using the Storage_Size aspect. Allocate as much stack space as you need to be able to do the calculations and do all the allocations on the declared task, not on the environment task. You will avoid the unnecessary heap allocations and have nice clean syntax. 
> 
> Best regards, 
> Joakim

Thank you for your reply, 
since I am a newbie I was under the impression that tasks are used only when you want to write a parallel code that takes advantage of multicore architectures. You suggest I have a single task and single thread something like this? I see, but there should be a way to do this also for the main program. But thanks anyway. Are you aware of any libraries similar to Real_Arrays, but who allocated memory internally using heap? This is the natural way to do such things. Similarly to the Containers.Vector. But Vector has such an awful syntax. There should be something like an indexer [i] similarly to the C++ std::vector to make things simpler and overloaded operators similarly to Real_Arrays. It is a no brainer. Most programs need to allocate on the heap, why did they restrict Real_Arrays on the stack?