[GAP Forum] arithmetic in C

[MCKAY john]

I point out that there is a nice method of John Dixon
for exact computation with cyclotomic integers by working
over a well chosen finite field F_p.

For algebraic integers there is the example of Darmon, Ford for
reconstructing exact values using p-adics. This is in Comm in Algebra
 17, (1989).

Lattice reduction may also be used.

John McKay