On 05/22/11 10:53, petros wrote:
Hi Larry, apologies, for not being clear. No problem.
Yes, MA is boost::multi_array. M, N, L are the dimensions (this is only a "logical" statement, rather than a proper code snippet).
I think I have pretty much sorted out the calling practices wrt multi-aray and looking for if certain functionality exists.
My problem amounts to having a view that would allow for the permutation (if not rotation) of axes.
I'm not sure I understand permutation and rotation. For example, say you have: multi_array<T,2> ma2(extents[3][4]); The array would have 3 rows and 4 columns. Now, since there are only 2 axes (row and column) permuting the axes would be transposing the matrix. Is that right. In general, for: multi_array<T,N> maN(extents[L[0]][L[1]]...[L[(N-1)]]); a permutaion of the axes could be specified by a permutation, p, of: (0,1,...,N-1) and the resulting array, maT, would satisify, for all: unsigned i[N]; such that for all axis in (0...N-1), i[axis]<L[axis]: maN[i[0]][i[1]]...[i[N-1]] == maT[i[p[0]]][i[p[1]]]...[i[p[N-1]]] If this is what you mean, then this could be done using the stepper data structure mentioned here: http://article.gmane.org/gmane.comp.lib.boost.devel/218623/match=index_list The q_i in that post corresponds to the p vector (which is a permutation of (0...N-1) mentioned above. The book referenced in that post also has a section on rotation; hence, it may be useful for that also. [snip]
I hope this is clearer now - don't mean to drag you into my problem. Thank you for your response, [snip]
You're welcome, Petros. HTH. -Larry