Numerical Algorithms

, Volume 12, Issue 2, pp 259–272 | Cite as

Rational approximations, software and test methods for sine and cosine integrals

  • Allan J. MacLeod


Rational approximations to the sine integralSi(x) and cosine-integralCi(x) are developed which give an accuracy of 20sf. The robust construction of software for these functions is discussed, together with a test procedure for assessing the performance of such codes. Use of the tests discovers a major error in the netlib library FN codes forSi. Fortran versions of the codes and tests are available by electronic mail.


Sine-integral cosine-integral rational software testing 

Subject classification

65D20 65V05 41A20 33A10 


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Copyright information

© J.C. Baltzer AG, Science Publishers 1996

Authors and Affiliations

  • Allan J. MacLeod
    • 1
  1. 1.Department of Mathematics and StatisticsUniversity of PaisleyPaisleyScotland

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