An algorithm is described that approximates complex numbers by elements of the algebraic integers of 
![Z[e^{2 \\pi i / 8}]](/images/tex/6024.gif)
 with integer coordinates of at most a prescribed size. The motivating application is to reduce the dynamic range requirements of residue number system implementations of the discrete Fourier transform. The closest points to zero of 
![Z[e^{2 \\pi i / 8}]_{M}](/images/tex/6025.gif)
 gor any integer 

 are determined. A particular sequence of such points forms the basis of the algorithm. An example of 

 -bit 
![Z[\\omega ]_{M}](/images/tex/6026.gif)
 - approximations of the 128th roots of unity is considered. The algorithm yields 

 with scaling 

 is reduced to 

 .