# AI Help!

G

#### Guest

##### Guest
hi!
i got a formula that i don't quiet understand, coursework, can anyone help

thanks, appreciate lots if you can help
the formula and its descriptions are in a blog please check the link
A Team!

i also uploaded a image of the formula.
info:
There is a list of n items that are to be send to the location where a certain container is going to (individual lists for each group will be put on the VLP). Each item i is only available once and has an associated weight wi, a volume vi, and a value, which is referred to here as fitness fi. Your task is to write a computer program that can find a list of items that a) fit into the container space available, not exceeding the maximum load wmax or the maximum volume vmax, and b) to maximise the total value ftotal of that shipping:

thanks

G

#### Guest

##### Guest
hi!
i got a formula that i don't quiet understand, coursework, can anyone help

thanks, appreciate lots if you can help
the formula and its descriptions are in a blog please check the link
A Team! http/teamntu.blogspot.com/

i also uploaded a image of the formula.
info:
There is a list of n items that are to be send to the location where a certain container is going to (individual lists for each group will be put on the VLP). Each item i is only available once and has an associated weight wi, a volume vi, and a value, which is referred to here as fitness fi. Your task is to write a computer program that can find a list of items that a) fit into the container space available, not exceeding the maximum load wmax or the maximum volume vmax, and b) to maximise the total value ftotal of that shipping:

thanks

#### Rusting In Peace

##### Distinguished
I remember doing a similar practical and I've totally forgotten the name of the algorithm / problem that this is formally called. Basically you are trying to get the most value from selected items without carrying too much weight or not being able to fit it in a space.

I think the traditional concept behind this is a bank heist. You as a robber must decide what is best to steal to make the most money with being able to fit everything in your van without the weight breaking the van. In terms of fitting everything in don't think of how to pack the items just assume everything is packed perfectly and you only have to ensure the total stole items' volume is less than the van's.

However the formulas are fairly straightforward.

The capital sigma character here means the sum of. Typically you put the limits of the sum on the bottom and top of the sigma. So i=1 to n is "the sum of all the items".

The lower case delta character is just a variable that can be 1 or 0. Here it's being used to modify the sum if the item is included or not. This should actually be delta with an i since the delta is not a constant across all the items! But I digress...

So in terms of the three formulas:

The total fitness is the sum of the fitness of selected items. If it helps you, think of fitness as "item value".

The maximum weight is less than the weight of the selected items. Or in the scenario where all items are selected the maximum weight is exactly equal to the total of all the items. I don't believe this formula is actually the maximum weight. I think this is the current weight.

The maximum volume function is basically the same but for select items' volume. Again I think this is actually a function for current volume.