by **Lomn** on Sat 01 Nov 2014 10:58

So, with the caveat that Month 5 isn't fully written yet (one of my complaints with this platform is that I haven't found a good way to create pages in private before publishing them):

"Eridani" typo corrected to "Centauri". "79 PTU" typo corrected to "78 PTU".

Eden does get a roll to see if a Governor is created, as it will cross the threshold from Settlement to Small with the colonists arriving this turn. Crossing that threshold also means that the PTU/PU conversion will no longer be 1:1. I'll document that in detail in the next month (since I'm showing that work at the top of each month), but here's how it'll work:

Eden has 150.7 PU now, and is adding 40 PTU. First, we convert Eden's PU to PTU, per Table L1.02: 150.7. OK, that was simple. Now add the new PTU: 190.7. Now we start working up the L1.02 conversion chart: 190.7 PTU is in the range for Small, and so we take the maximum PTU size for the next smallest population (Settlement, 180) and subtract that from the overall PTU: 180 PTU gets us to the end of Settlement, and the remaining 10.7 PTU must be converted into a Small population's PU at the listed rate. That comes to 5.3 PU, and so the population size becomes 180 PU (the max size Settlement) plus 5.3 PU (the portion within the Small block) for 185.3 PU overall.

A more complex example would be colonizing a Medium world: a 995 PU world adds 270 PTU in colonization. 995 PU converts to PTU by taking the size of the largest possible smaller population (Small, 500 PU, 820 PTU) and converting the remainder at the current size rate (Medium, 495 PU, 1 PU to 10 PTU, 4950 PTU). So, 5770 PTU now, plus 270 new PTU: 6040 PTU overall. Working the other way, the largest population that fits within 6040 PTU is Medium (5820 PTU, 1000 PU), so we take that off and convert the remaining 220 PTU at Large rates (1 PU to 70 PTU, 3.1 PU). The new population is Large and 1003.1 PU.

In working this out, I notice that I've skipped a footnote in Table L1.02 about truncating fractional PTU values (which means truncating fractional PU values in many cases). Should this apply to the basic rule for population growth? This footnote says "for purposes of using this table", and basic growth (1% gain to the tenth of a PU) doesn't care about this table, so I'm going with "no" -- and by extension, saying that the tutorial's examples of a 5 PU world growing by 0.1 PU (and thus by 0.1 PTU) per month are fine, and that the scope of this "truncate" footnote is just to clear up gray areas like the size of a 60.5 PU world. That might be wrong, but it's a pretty minor deviation, and so long as everybody in a game plays it the same way, it's not likely to matter.