spatial analysis

Dear all,

I am a PhD student in energy modelling. I am completely stuck with the
following problem and would be very grateful for any kind of help.
I have cells

Don't we all?  We're made of them. :-)

     What do you mean by ``I have''?  I.e. be a bit more explicit about
     the nature of your data.

and each cell is assigned a number. I would like to form
clusters of cells where the sum of the cell numbers in each cluster must
not exceed 250. One restriction is that only neighbouring cells

Define "neighbouring".

can be
formed into clusters. In the end I would like to have a list with all
possible cell combinations.

Do you mean all possible ways in which your ``collection of cells''
     can be subdivided into such clusters?  My guess is that the number
     of such ways could be extremely large.  (Depending of course on
     how many cells there are in the collection.)

Is it possible to do this with R If yes, I would very much appreciate
all possible hints how to solve it.

Install the "fortunes" package.  Then type

         fortune("Yoda")

     But if you want useful help you'll have to make your question much
     clearer.

         cheers,

             Rolf Turner