Hankel Transform

Routine to perform a QDHT with no limit on data size or transform order (other than memory constrain

This file contains 2 functions:
bessel_zeros - finds zeros of a bessel function
hankel_matrix - generates a structure of data to use for Hankel transforms

The algorithm is taken from:
M. Guizar-Sicairos and J. C. Gutierrez-Vega, Computation of quasi-discrete Hankel transforms of integer order for propagating optical wave fields,
J. Opt. Soc. Am. A 21, 53-58 (2004)

An example of beam propagation with circular symmetry has been written in the hankel_matrix help:
Type "help hankel_matrix" or "doc hankel_matrix" in Matlab.