The code is based on collocation at either equidistant
or Gaussian collocation points. For singular problems,
the choice of equidistant nodes does not imply a loss
of efficiency since no convergence order higher than
the stage order can be expected in general. An error
estimate for the global error of the approximate
solution is also provided. This estimate is obtained
by a modification of an idea due to Frank and
Überhuber ([2]), who generalized an
error estimate originally proposed by Zadunaisky
([3]). Our new estimate was introduced
in [1], where its asymptotic
correctness was also discussed. This estimate is the
basis for an adaptive mesh selection strategy which
proved robust with respect to the singularity. We
discuss details of the efficient implementation in
MATLAB 5.3, give a preview of a MATLAB 6.0
version, and illustrate the performance of the code.