Abstract: A Fortran 90 program for the computation of the real parabolic cylinder functions W(a, ± x), x ? 0 and their derivatives is presented. The code also computes scaled functions for a > 50. The functions W(a, ± x) are a numerically satisfactory pair of solutions of the parabolic cylinder equation y? + (x2/4 ? a)y = 0, x ? 0. Using Wronskian tests, we claim a relative accuracy better than 5 10?13 in the computable range of unscaled functions, while for scaled functions the aimed relative accuracy is better than 5 10?14. This code, together with the algorithm and related software described in Gil et al. [2006a, 2006b], completes the set of software for Parabolic Cylinder Functions (PCFs) for real arguments.

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