Identifying the start of good data in a list

[castironpi]

On Aug 29, 9:43 am, Jorgen Grahn <grahn+n... at snipabacken.se> wrote:
> On 27 Aug 2008 15:50:14 GMT, Steven D'Aprano <st... at REMOVE-THIS-cybersource.com.au> wrote:
>
>
>
> > On Tue, 26 Aug 2008 17:04:19 -0700, tdmj wrote:
>
> >> On Aug 26, 5:49 pm, tkp... at hotmail.com wrote:
> >>> I have a list that starts with zeros, has sporadic data, and then has
> >>> good data. I define the point at  which the data turns good to be the
> >>> first index with a non-zero entry that is followed by at least 4
> >>> consecutive non-zero data items (i.e. a week's worth of non-zero data).
> >>> For example, if my list is [0, 0, 1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9], I
> >>> would define the point at which data turns good to be 4 (1 followed by
> >>> 2, 3, 4, 5).
>
> He has a point though: this *can* be seen as a regex problem. Only a
> solution which builds a string first is only good for laughs or
> (possibly) quick hacks. What's missing is an RE library for lists of
> objects, rather than just strings and Unicode strings.
>
> Not sure such a library would be worth implementing -- problems like
> this one are rare, I think.

Every now and then, you see a proposal or a package for a finite state
machine--- how would you encode comparing of values into a string, if
you're not comparing a string?