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Chebyshev approximations for the psi function


Authors: W. J. Cody, Anthony J. Strecok and Henry C. Thacher
Journal: Math. Comp. 27 (1973), 123-127
MSC: Primary 65D15
DOI: https://doi.org/10.1090/S0025-5718-1973-0326986-3
MathSciNet review: 0326986
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Abstract | References | Similar Articles | Additional Information

Abstract: Rational Chebyshev approximations to the psi (digamma) function are presented for $ .5 \leqq x \leqq 3.0$, and $ 3.0 \leqq x$. Maximum relative errors range down to the order of $ {10^{ - 20}}$.


References [Enhancements On Off] (What's this?)

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Additional Information

DOI: https://doi.org/10.1090/S0025-5718-1973-0326986-3
Keywords: Psi function, digamma function, rational Chebyshev approximation
Article copyright: © Copyright 1973 American Mathematical Society

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