Abstract
The quadrature formulas described by James Gregory (1638–1675) improve the accuracy of the trapezoidal rule by adjusting the weights near the ends of the integration interval. In contrast to the Newton–Cotes formulas, their weights are constant across the main part of the interval. However, for both of these approaches, the polynomial Runge phenomenon limits the orders of accuracy that are practical. For the algorithm presented here, this limitation is greatly reduced. In particular, quadrature formulas on equispaced 1-D node sets can be of high order (tested here up through order 20) without featuring any negative weights.
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Notes
Gregory’s letter of 1670 (to John Collins, written mostly in English) indeed begins with “I suppose these series I send you here enclosed, may have some affinity with those inventions you advertise me that Mr. Newton have discovered.” Only extracts of the letter are preserved. These do not include Gregory’s derivation.
References
Advanpix: Multiprecision computing toolbox for MATLAB. Advanpix LLC, Yokohama, Japan. http://www.advanpix.com/. Accessed 8 Aug 2018
Bailey, D.H., Borwein, J.M.: High-precision numerical integration: progress and challenges. J. Symb. Comput. 46, 741–754 (2011)
Bayona, V., Flyer, N., Fornberg, B., Barnett, G.A.: On the role of polynomials in RBF-FD approximations: II. Numerical solution of elliptic PDEs. J. Comput. Phys. 332, 257–273 (2017)
Bocher, P., De Meyer, H., Berghe, G.: On Gregory- and modified Gregory-type corrections to Newton–Cotes quadrature. J. Comput. Appl. Math. 50, 145–158 (1994)
Brunner, H., van der Houwen, P.J.: The Numerical Solution of Volterra equations. CWI Monographs. Elsevier, Amsterdam (1986)
De Swardt, S.A., De Villiers, J.M.: Gregory type quadrature based on quadratic nodal spline interpolation. Numer. Math. 85, 129–153 (2000)
De Villiers, J.: Mathematics of Approximation. Atlantis Press, Amsterdam (2012)
De Villiers, J.M.: A nodal spline interpolant for the Gregory rule of even order. Numer. Math. 66, 123–137 (1993)
Fornberg, B.: A Practical Guide to Pseudospectral Methods. Cambridge University Press, Cambridge (1996)
Fornberg, B., Flyer, N.: A Primer on Radial Basis Functions with Applications to the Geosciences. SIAM, Philadelphia (2015)
Fornberg, B., Flyer, N.: Solving PDEs with radial basis functions. Acta Numer. 24, 215–258 (2015)
Fraser, D.C.: Newton’s interpolation formulas. Further notes. J. Inst. Actuar. 52(274), 117–135 (1920)
Gregory, J.: Letter to J. Collins, 23 November 1670, pp. 203–212. In: Rigaud: Correspondence of Scientific Men. Oxford University Press (1841)
Javed, M., Trefethen, L.N.: Euler–Maclaurin and Gregory interpolants. Numer. Math. 132, 201–216 (2016)
Jordan, C.: Calculus of Finite Differences, 2nd edn. Chelsea, New York (1950)
Phillips, G.M.: Gregory’s method for numerical integration. Am. Math. Mon. 79(3), 270–274 (1972)
Pólya, G.: Über die Konvergenz von Quadraturverfahren. Math. Zeitschrift. 37, 264–286 (1933)
Reeger, J.A., Fornberg, B.: Numerical quadrature over smooth surfaces with boundaries. J. Comput. Phys. 355, 176–190 (2018)
Romberg, W.: Vereinfachte numerische Integration. Det Kongelige Norske Videnskabers Selskab Forhandlinger 28(7), 30–36 (1955)
Takahasi, H., Mori, M.: Double exponential formulas for numerical integration. Res. Inst. Math. Sci. 9, 721–741 (1974)
Trefethen, L.N.: Approximation Theory and Approximation Practice. SIAM, Philadelphia (2013)
Trefethen, L.N., Weideman, J.A.C.: The exponentially convergent trapezoidal rule. SIAM Rev. 56, 384–458 (2014)
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Support received from Department of Defense, the Office of Naval Research (Atmospheric Propagation Sciences of High Energy Lasers) and the Air Force Office of Scientific Research (Radial Basis Functions for Numerical Simulation). The views expressed in this article are those of the authors and do not reflect the official policy or position of the United States Navy, Department of Defense, or U.S. Government.
Appendix: Derivations of the alternate matrix formulation
Appendix: Derivations of the alternate matrix formulation
1.1 Derivation based on Eq. (10)
Changing variable \(z=-\log (1-w)\) in (10) gives
By (5), the LHS above equals \(\sum _{i=0}^{\infty }(-1)^{i}b_{i}\). Equating coefficients gives (13).
1.2 Derivation based on matrix algebra
There are numerous exact relations for Vandermonde matrices, especially in equi-spaced cases. Starting by LU-factorizing it, it transpires that the linear system (12) can be rewritten as
The entries in the second matrix in the RHS are the first order Stirling numbers \(S(i,j),\;i,j=0,1,2,\ldots \), with generating function
These numbers are readily calculated by the ’Pascal-like’ recursion \(s(i,j)=s(i-1,j-1)-(i-1)s(i-1,j)\), initiated by the trivial values when \(i=0\) and \(j=0\). By the identity
([15]; combine (7), p. 147 with (5), p. 249), the RHS of (18) simplifies to
There is now a leading minus sign, both matrices have been shifted one step up and left, and the RHS vector has become much simplified. The result
now follows from combining (7) and (19) with the additional observation that integration in x of the monomials \(x,\,x^{2},\,x^{3},\,\ldots \). produce the factors \(\frac{1}{2},\,\frac{1}{3},\frac{1}{4},\,\ldots \) , matching the RHS vector in (20). The equality of the right hand sides of (18) and (21) can alternatively be deduced from equation (8) in [16].
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Fornberg, B., Reeger, J.A. An improved Gregory-like method for 1-D quadrature. Numer. Math. 141, 1–19 (2019). https://doi.org/10.1007/s00211-018-0992-0
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DOI: https://doi.org/10.1007/s00211-018-0992-0