Amos, D. E. A portable Fortran subroutine for derivatives of the psi function. (English) Zbl 0519.65013 ACM Trans. Math. Softw. 9, 494-502 (1983). Page: −5 −4 −3 −2 −1 ±0 +1 +2 +3 +4 +5 Show Scanned Page Cited in 3 Documents MSC: 65D20 Computation of special functions and constants, construction of tables 33-04 Software, source code, etc. for problems pertaining to special functions 33B15 Gamma, beta and polygamma functions Keywords:psi function; gamma function; derivatives of the gamma function; zeta function; single-precision subroutine; double-precision subrutine Software:PSIFN PDFBibTeX XMLCite \textit{D. E. Amos}, ACM Trans. Math. Softw. 9, 494--502 (1983; Zbl 0519.65013) Full Text: DOI Digital Library of Mathematical Functions: In §5.24(iii) 𝜓(𝑥), 𝜓^(𝑛)(𝑥), 𝑥∈ℝ ‣ §5.24 Software ‣ Computation ‣ Chapter 5 Gamma Function