Just read your second post again. You are not selling by meter like we do (so 1 meter, 2 meters, 3 meters etc) but you want options between those, 1.1,1.2,1.3 etc - Only with combinations I am afraid. Read up on it, as the system will allow you to auto generate those combinations (You can also use the Product Combinations Generator in order to automatically create a set of combinations.)
The main problem I see with this kind of thing is stock control. If the seller has 10 meters, and sells it in 1.1, 1.2, 1.3 ,meters etc then what happens in this scenario
Customer 1 purchases the full 10 meter
BUT
Customer 2 can still purchase 1.1 meter
Until someone (or something) then re-adjusts all the stock values of the combinations