06-02-2003 21:49									#1
	Population growth rate? Support Apolyton buy from Amazon

I have a Q that I can't seem to find the answer to in thje forum or the models on the homepage:

What governs the growthrate of the pop in a given square, and how does the player have an influence on it?

I think this should be one af the basic skills learned in Dawn and plan to include it, so I need to know where I kan find a detailed description of it.

Last edited by Martin the Dane on 06-02-2003 at 22:07

	06-02-2003 22:08									#2
	Increase Your PM Length

Hi Martin:

Well, all kinds of things will eventually be included for population growth or decline. Those things include sanitation, standard of living, food, etc.

Here is what is used now, which depends only on food. I have used the variable names in the code since I'm in a hurry. growthRate is mis-named. The factor of .001 comes from the fact that the economy uses units of "heads" which are 1000 people, whereas population is in terms of individuals:

foodEatenPerHead = food / population
modifier = 0.001 / (foodEatenPerHead + 0.001)
growthRate = 1.04 - modifier^2
new population = population * growthRate

Basically foodEatenPerHead = 4/1000 is subsistence, and the population neither declines or grows (growthRate =1)

With infinite food the population grows at 4% per turn (growthRate = 1.04)

With food below 4/1000 the population declines due to malnutrition or outright starvation.

Food available for the people to eat is usually less than food produced, since army supplies and some other economic activites also consume food.

Hope that's enough!

	07-02-2003 01:06									#3
	Increase Your PM Length

Btw, I would like the growth model to be more detailed so I can get real sieges working. The square in square stuff can't be coded if I don't have some supplies/food trade/whatever to represent resources inside the fortress and what is outside (typically, if food is 0 with the current model, population is reduced to 0.04 times what it used to be, which doesn't allow for long sieges - not counting effect on troops).

	07-02-2003 03:53									#4
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Thanks for the explanations. I guess what I'll do is tell the player that there eventually will be a lot of factors influencesing pop-growth, but at the pressent only food is implemented. And encourage the player to invest in food increasing activity, like farm research etc. I'll have to think about how to do this.

Mark, I hope "new population" refers to the number of pop in this turn based on last turns numbers, and not the number of pop added.

Laurent, are you thinking of food storage like in graneries etc. as oposed to "surpluss" food used for growth in the turn?

Will there evenually be "buildings" that can be built in provinces/squares that influences growth and starvation.

btw. is there a growthRate thread, or sould I (and others) post suggestions here?

	07-02-2003 05:43									#5
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quote: Originally posted by LDiCesare Btw, I would like the growth model to be more detailed so I can get real sieges working. The square in square stuff can't be coded if I don't have some supplies/food trade/whatever to represent resources inside the fortress and what is outside (typically, if food is 0 with the current model, population is reduced to 0.04 times what it used to be, which doesn't allow for long sieges - not counting effect on troops).

Sure Laurent. Why don't you go ahead and go as far on the square-within-square as you can, and then I'll figure how to make the food not disappear! I hope to be set again for coding early in the weekend, but I can't promise.

quote: Originally posted by Martin the DaneMark, I hope "new population" refers to the number of pop in this turn based on last turns numbers, and not the number of pop added.

Yes

quote: Will there evenually be "buildings" that can be built in provinces/squares that influences growth and starvation.

I was thinking of a "social welfare" class that could store food and other materials for times of need, or to any unemployed when the model gets that far.

quote: btw. is there a growthRate thread, or sould I (and others) post suggestions here?

There have been discussions before in a variety of places. You should be able to find them by searching on a variety of relevant terms. But seeing as this thread has gotten this far we might as well keep it. If you find old threads please post links in your first post so we can get at the old discussions.