Group array elements based upon their differences

I have an array

x=[20 18 16 14 11 9 6 3 2 1]

I can find the intermediate difference of the array elements by

x1=-diff(x)

x1=[2 2 2 3 2 3 3 1 1]

Now based upon x1 value, I can group/partition,

x (that array)

in 4 parts where there is a variation of their mutual differences

such that

c1={20,18,16,14} 
c2={11}
c3={9,6}
c4={3,2,1}

what shall be my programming logic so that I could partition it 3 or 5 groups as well.

thanks

[joy]

SplitVec

might help... Link for SplitVec