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Postings from September 2000
c.soeller@auckland.ac.nz wrote: > Reading through the examples left me wondering about some > technicalities: > > > @t[|i;|j] = @a[|j;|i]; # transpose 2-d @a > > Written like this it would require that @a is exact 2-dim, i.e. it would > not just swap the first two dims of any n-dim array? I suppose if I'd > want that I'd write > > @t[|i;|j;] = @a[|j;|i;]; # trailing ';' implies there might be > trailing dims > Not necessary. Since arrays support all the syntax of a plain old list of lists, and the |i syntax just creates an implicit loop, the example quoted from the RFC will work with other sized arrays. In fact, if it was only 2d, it would more properly be: $t[|i;|j] = $a[|j;|i]; # transpose 2-d @a With three dimensions, each implicit loop in @t[|i;|j] = @a[|j;|i]; # transpose 2-d @a is assigning the _list_ (or 1d array) at @a[|j;|i] to the appropriate index in @t. Ditto for >3 dimensions, except that it is a >1d array (or LOL) that is being assigned at each index through the implicit loop.