Abstract
The solution of many problems in radiative transfer and transport theory, requires calculations of real-order exponential integrals,E s (x). We consider a composite algorithm based on a recursive evaluation ofE s (x),\(s \in \mathbb{R}\),x>0, starting from a suitable initial value in the region of positives andx arguments, which ensures the numerical stability of the involved recurrences.
Zusammenfassung
Die Lösung vieler Probleme in der Transportheorie und Strahlungsübertragung erfordert die Auswertung von ExponentialintegralenE s (x) reeller Ordnung. Wir betrachten einen mehrteiligen Algorithmus zur rekursiven Berechnung vonE s (x),\(s \in \mathbb{R}\),x>0, der von einem geeigneten Anfangswert im Bereich positivers undx ausgeht, der die numerische Stabilität der Rekursion garantiert.
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Chiccoli, C., Lorenzutta, S. & Maino, G. An algorithm for exponential integrals of real order. Computing 45, 269–276 (1990). https://doi.org/10.1007/BF02250638
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DOI: https://doi.org/10.1007/BF02250638