A new algorithm for the evaluation of the incomplete gamma function on vector computers

ABSTRACT

Several methods of evaluating the Incomplete Gamma Function are compared according to accuracy and computation time. An improved algorithm is presented which allows significantly faster computation of two-electron integrals on most vector computers, especially in the case of GLO functions. Parameters for F0(t) are tabulated.

REFERENCES

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INDEX TERMS

Primary Classification:
  G. Mathematics of Computing
  G.4 MATHEMATICAL SOFTWARE
      Subjects: Efficiency

Additional Classification:
  C. Computer Systems Organization
  C.1 PROCESSOR ARCHITECTURES
      C.1.2 Multiple Data Stream Architectures (Multiprocessors)
          Subjects: Array and vector processors

  G. Mathematics of Computing
  G.1 NUMERICAL ANALYSIS
      G.1.2 Approximation
          Subjects: Rational approximation
  G.4 MATHEMATICAL SOFTWARE
      Subjects: Algorithm design and analysis

  J. Computer Applications
  J.2 PHYSICAL SCIENCES AND ENGINEERING
      Subjects: Chemistry

General Terms:
Algorithms, Performance

Keywords:
Incomplete Gamma Function, quantum chemistry, two-electron integrals