Matthew Rhys-Roberts wrote:

> Sean Breheny wrote:
>> Just beware that you need a data type which is large enough to store x^2
>> to do this. You might be better doing c*x first and then multiplying by
>> x again. That minimizes the range of values which your variables need
>> to store.
> 
> Yes. Luckily, my x is a 16 bit unsigned integer, so x^2 always fits in a
> 32 bit space. I hadn't considered the benefits of working out c*x*x in
> that sequence however. 

Yes, you always have the choice where to place the multiplications and
divisions. You can also split up a division by 2^16 into two divisions by
2^8, in two different stages of the calculation. This can affect the
precision of the result and the possible range of the inputs.

Gerhard

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