While in some cases there's an advantage of storing the increments instead of the values (it can save space - a technique also used in sampling (but there's not much to gain in Perl, except when your numbers would have been BigInts and your increments aren't)), I don't see the advantage of your complicated first value. Why not add an imaginary 0 before the orginal list and store just the differences? (That means, the first value is the first value). The you only need one pass in both the decoding and encoding.

Abigail

In reply to Re: Perl Drag Racing - sum/delta list by Abigail-II
in thread Perl Drag Racing - sum/delta list by John M. Dlugosz

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