# MATLAB codes

We provide two easy to use MATLAB codes for computing resoances in one dimension. A more complete package which allows refinement of parameters (necessary for some computations) is available at

An example of the use of the first code is given in Fig.1. The data is a vector of values,

and a vector of points

and

squarepot( )

computes the first (or so, depending on 's and 's) resonances for with

An example of using the second code is given in Fig.8. The data now are two vectors of the same length and

splinepot( )

computes the first (or so, depending on 's and 's) resonances for given by a cubic spline interpolating between the values at , clamped at and (that is ), and , for . If

The approximation of a smooth potential can still provide a good accuracy of resonances relatively close to the real axis - see Fig.8 and [4].

David Bindel 2006-10-04