> On Fri, May 25, 2001 at 02:34:05AM -0400, Alexander Viro wrote:
> > Should we file bug reports against glibc?
>
> invsqrtpi= 5.64189583547756279280e-01
> Inverted square root of pi. Want to file a bug on Pi?
>
> tpi = 6.36619772367581382433e-01,
> R0/S0 on [0, 2.00]
>
> I'm not sure what R and S are, but the glibc developers probably are.
We have comments in the code that state how j0 is build, and R0/S0
come from some expansion:
* Bessel function of the first and second kinds of order zero.
* Method -- j0(x):
* 1. For tiny x, we use j0(x) = 1 - x^2/4 + x^4/64 - ...
* 2. Reduce x to |x| since j0(x)=j0(-x), and
* for x in (0,2)
* j0(x) = 1-z/4+ z^2*R0/S0, where z = x*x;
* (precision: |j0-1+z/4-z^2R0/S0 |<2**-63.67 )
Andreas
-- Andreas Jaeger SuSE Labs aj@suse.de private aj@arthur.inka.de http://www.suse.de/~aj - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/