[Gretl-devel] operators on arrays of strings

For a project I was working on today it seemed it would be useful to have a couple of operators defined for strings arrays, so I went ahead and implemented them. First, for an array of strings S and a single string s: S .= s returns a vector of the length of S, with 1s in positions where s is matched, 0s otherwise. This is similar to the instrings() function but gives the information in a different form that may be more convenient in some cases. Plus, S .!= s gives the complementary vector. Second, S2 = S - s returns an array of strings obtained by removing all elements of S that match s. If you want to modify S rather than construct a new array, then S -= s does the job -- with greater efficiency, since the removal is done in-place, requiring no extra memory allocation. These will be documented in due course. Allin