Linear programming question

1. Apr 24, 2014

timeone

I have a problem at work I'm trying to solve and I can't figure out a good way to do it, hoping someone might be able to help. I have put the relevant info in the below pastebin. Basically I want to distribute some amount of S into two bins, one of which is split into smaller bins, in such a way that the amount between the two is as close to some give ratio as it can be, and then the amount in the first larger bin is split as close as equally among the smaller bins inside of it.

I was thinking about the Simplex algorithm but not sure how well it would work...

http://pastebin.com/wsR86rev [Broken]

Last edited by a moderator: May 6, 2017
2. Apr 24, 2014

WWGD

Sorry, I'm confused; seems you're defining $S_b$ in terms of itself?

3. Apr 25, 2014

Staff: Mentor

From Pastebin at the link above:
This is gibberish until you tell us more clearly what you're trying to do.

Last edited by a moderator: May 6, 2017
4. Apr 25, 2014

timeone

Hi Mark,
Sorry for being too vague, I was trying to reduce it into a series of equations to make the linear algebra problem more clear. I'll give an example:

Suppose $S$ is the total budget say \$100, $S$ should be split into two sub groups, $S_a$ and $S_b$. $S_a$ contains sub groups, $G_1$ through $G_n$, and $G_i$ = $c_i$*$I_i$. Think of $c_i$ as some fixed cost per item for a group of items $I_i$. The second top level group, $S_b$, is the spillover group. Give some percentage, say r=30%, I'd ideally like 30% of the items in group $S_a$ and 70% in group $S_b$. This doesn't necessarily mean the budget is split 30/70, just the items. Only so many items can fit in each sub-group( $I_i$ <= $k_i$ ). If not all the items can fit in $S_a$ , put them in the $S_b$ along with the other 70%.

Basically I'm trying to figure out how many items can go in each group, keeping the ratio of items between $S_a$ and $S_b$, keeping an even split of items between all sub-groups $G_i$, and having the sum of all groups equal the total budget.