A fast and stable numerical algorithm is presented for the interpolati
on from an arbitrary Jordan curve in the complex plane to the region b
ounded by that curve. The algorithm combines the classical analytical
apparatus with the fast multipole method to obtain an order O(N-1.5) p
rocedure for the determination of interpolation nodes with N the numbe
r of nodes in the discretization of the given curve and order O(M + K)
procedure for the actual interpolation from M nodes on the boundary o
f the region to K nodes inside the region. The performance of the algo
rithm is illustrated with several numerical examples. (C) 1991 Academi
c Press.