Integer Math error reduction techniques

Using Arduino Project Guidance
1

Hello,

I want to implement the Bilinear interpolation in arduino and accuracy is very important. Bilinear interpolation - Wikipedia
Is there a to keep precision while doing the calculations in integers?

Thanks

2

Refer to: http://www.gammon.com.au/forum/?id=11519

3

Is there a to keep precision while doing the calculations in integers?

There is a whole branch in computer science - numerical methods - trying to keep precision in computer math including integers, floats, doubles, complex etc.

using bigNumber is a very good solution although it has some performance consequences.

if you want to keep the math in integer domain, you can multiply all numbers by X and later divide the result by X.
This is sort of doing math with an extra decimal. This works unless the multiplication causes overflow.
If you take a power of 2 (e.g. 32) the performance penalty is quite low.
(do not forget proper rounding in the end)

Can you tell us what the table looks like?
Ranges X and Y axis?
nr of cells?
is it filled with integers?
how far are they apart? (is integer interpolation possible)
do you want the result to be an integer or a float?