[Gretl-devel] Re: new operation on string-valued series

Am 16.10.20 um 23:53 schrieb Allin Cottrell: This is pretty useful, Allin! I often face the "problem" that I have two or more string-valued series which need to be concatenated for creating a unique identifier before one can set a panel structure. I also ran the script below with a slightly modified data set where column "tension_w_nan" includes an NA value. In this case the resulting series is NA as well which makes somehow sense as multiplying a valid number with NA yields NA. I guess that's as expected given the current implementation. <hansl> open "../tmp/warpbreaks.csv" series wt = wool * tension series wt2 = wool * tension_w_nan series tw2 = tension_w_nan * wool print wt tension_w_nan wt2 tw2 -o </hansl> However, one comment on the current syntax/ implementation using the asterisk symbol: In Python/Pandas (we don't have to mimic that behavior though!) string concatenation is usually done by the summation symbol: <series sv3 = sv1 + sv2> -- at least that's my experience. In case one of the RHS variables is NA, let's say sv1[i]=NA, you still get sv3[i]=NA+sv2[i] which equals the string value of sv[i]. Also, let me go even a step further. A more flexible version may be a function with three arguments: "sv1", "bridge" and "sv2" where "bridge" (not the most ideal parameter name) may be optional allowing for a user-defined bridging string such as underscore ("_") in the current implementation. Artur