Re: Calculations while sorting?

[Ben Pfaff]

John Darrington <address@hidden> writes:

> How feasible would it be to have sort_execute optionally calculate
> some simple linear statistics on the fly?  eg: the sum of values in
> one column.
>
> If that could be done, then it would avoid the need for an extra pass
> through the data for many procedures.

It would be easy to create a "moments_reader" that does calculations
like this as side effects and otherwise passes cases through
without modification.

There would be no need to make this part of sorting.  Just make a
"moments_reader" out of your data and then pass the
moments_reader to sort_execute.
-- 
Ben Pfaff 
http://benpfaff.org