Re: multi-array comments/questions

From: rgarcia1771 (garcia_at_[hidden])
Date: 2002-01-02 23:32:17

--- In boost_at_y..., nbecker_at_f... wrote:
> After a quick look at the multi-array doc, I have a couple of
> comments/questions.
> 

> 1)  More doc needed (no surprise).  Several times, there are 
comments
>     about "You can suppress this object by defining
>     BOOST_MULTI_ARRAY_NO_GENERATORS before including the library
>     header."  What does this mean?  What are the implications?

Including either of the multi_array headers (multi_array.hpp or 
multi_array_ref.hpp) instantiates two objects, boost::extents and 
boost::indices, that reside in an unnamed namespace under namespace 
boost. If multi_array is used in multiple source files, multiple 
copies of these objects may exist in an application. If this is a 
concern, the library user may #define the above symbol to inhibit 
their construction.

> 2)  It looks like an array view is a different animal than an array.
>     How can I make generic algorithms that work with either one?  Is
>     this desirable (I think it is)?

The array views and subarrays provide a similar interface to the 
multi_array and multi_array_ref.  I defined the concepts "Mutable 
Multi-Array" and "Const Multi-Array" to specify the generic interface 
to multi-dimensional array types. I did not want view or subarray 
implementation details to appear in the user or reference 
documentation where they were irrelevant to the PI.  I may have 
abridged my discussion of views and subarrays too much as a result.  

Cheers,

ron