How to replace empty rows until next entry (and continue)?

[#1]

Dear JMP community,

(W10, 64-bit, JMP 15.0 Pro)

  I have a large data table that is imported from an excel file and I need to have empty rows of a column filled with the entries of the previous list. I am trying to write JSL to go from a column as on the left to the one on the right, as shown below:

Snap1.png

  I'm thinking it should be pretty easy to code, but the issue I'm having is correctly stopping at the end of the previous product and starting with the new product. I must not be looping through correctly.

  Any suggestions/help is welcome.

Thanks!,

DS

[#2]

A couple of the JMP systems engineers were going round and round on this problem and this was the best solution. This final version by @Brady Brady is heads a tails faster and more robust than the simple formula we started with. I've been using it for years and found it to work well in a number of situations.  Glad it worked for you!