There is indeed a problem sage: legendre_P(2, 0) 1/2 sage: legendre_P(2.0, 0.0) -0.500000000000000
On Mon, 6 Jun 2022 at 20:38, Dan Cross <danieljcr...@gmail.com> wrote: > > Hi, > It seems the special values of the Legendre Polynomials evaluated at zero are > hard coded to be positive, but the sign should alternate. So, while > legendre_P(0,0) correctly gives 1 and legendre_P(4,0) correctly gives 3/8, > legendre_P(2,0) gives +1/2 instead of -1/2. Evaluating legendre_P(2,x) for > any x close to zero gives a value close to -1/2 as it should. This problem > is even evident on the documentation page > (https://paulmasson.github.io/sagemath-docs/functions/legendre_P.html) which > shows the graph of P_2 passing through -1/2 but tabulates the special value > at zero as +1/2. > > Thanks. > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sage-devel/9745505a-d332-4b63-9acd-770123e0291dn%40googlegroups.com. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/CAGEwAAndOc_J5r8AJSE4BuikdsiMv5Mt%3DpjGvPNc1Bjn32tdcQ%40mail.gmail.com.
