Bessel functions with negative inputs

When entering user-defined functions or equations, Prism offers four Bessel functions. Each of these functions has two inputs, X and N. The documentation for Prism 5 and 6 implied that N must be be a nonnegative integer, and the functions worked fine in when this was the case.

In fact, the Bessel functions also work with a negative N value as an input, but there were two bugs in Prism 6 with negative values of N

• For the Integer Order J Bessel function besselj(n,x) for n < -1, the result computed by Prism 6 had the correct value but with the opposite sign.
• For the Integer Order Y Bessel function bessely(n,x) for n = -1 Prism 6 calculated an incorrect value. For n < -1 the value was correct.

These bugs are fixed in Prism 7.