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digitalmars.D - Orthogonal Arrays

reply bmeck <bmeck stedwards.edu> writes:
I've been wondering how other people deal with this. Arrays that are distinct
and separate but related. I've heard people say why aren't you using a
structure of some kind, but in reality sometimes this is just not practical to
restructure lots and lots of data and the way to get to data can be messy. For
example, images can have multiple color planes (essentially a color plane can
be considered a nth dimensional array which is generally byte[][3] for 256
colors with 1 byte each representing a pixel), because of having multiple of
these planes is possible it could take a lot of moving to make a structure out
of every color plane's pixel array and combine it will all the others.

I was hoping someone out there could point me at a way to treat multiple
orthogonal arrays as a single structure (ie. if you have 2 arrays $A with
[name] and $B [with r,b,and g] members you could do $X = orthogonal!(A,B) then
use X[i].name and also X[i].r) without restructuring things in memory.
Nov 03 2008
parent BCS <ao pathlink.com> writes:
Reply to bmeck,

 I've been wondering how other people deal with this. Arrays that are
 distinct and separate but related. I've heard people say why aren't
 you using a structure of some kind, but in reality sometimes this is
 just not practical to restructure lots and lots of data and the way to
 get to data can be messy. For example, images can have multiple color
 planes (essentially a color plane can be considered a nth dimensional
 array which is generally byte[][3] for 256 colors with 1 byte each
 representing a pixel), because of having multiple of these planes is
 possible it could take a lot of moving to make a structure out of
 every color plane's pixel array and combine it will all the others.
 
 I was hoping someone out there could point me at a way to treat
 multiple orthogonal arrays as a single structure (ie. if you have 2
 arrays $A with [name] and $B [with r,b,and g] members you could do $X
 = orthogonal!(A,B) then use X[i].name and also X[i].r) without
 restructuring things in memory.
 

struct Orth(T...) { T[] t; // uses some template to make a tuple of arrays cell opIndex(int i) { return cell(this, i); } struct cell { Orth!(T)* base; int i; mixin(BodyOf!(T)) ;// extract memebers of T's and build accessors. } }
Nov 03 2008