Advances in Computational Mathematics

, Volume 5, Issue 1, pp 329–359 | Cite as

On the LambertW function

  • R. M. Corless
  • G. H. Gonnet
  • D. E. G. Hare
  • D. J. Jeffrey
  • D. E. Knuth


The LambertW function is defined to be the multivalued inverse of the functionwwe w . It has many applications in pure and applied mathematics, some of which are briefly described here. We present a new discussion of the complex branches ofW, an asymptotic expansion valid for all branches, an efficient numerical procedure for evaluating the function to arbitrary precision, and a method for the symbolic integration of expressions containingW.


Applied Mathematic Asymptotic Expansion Numerical Procedure Arbitrary Precision Symbolic Integration 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© J.C. Baltzer AG, Science Publishers 1996

Authors and Affiliations

  • R. M. Corless
    • 1
  • G. H. Gonnet
    • 2
  • D. E. G. Hare
    • 3
  • D. J. Jeffrey
    • 1
  • D. E. Knuth
    • 4
  1. 1.Department of Applied MathematicsUniversity of Western OntarioLondonCanada
  2. 2.Institut für Wissenschaftliches RechnenETHZürichSwitzerland
  3. 3.Symbolic Computation GroupUniversity of WaterlooWaterlooCanada
  4. 4.Department of Computer ScienceStanford UniversityStanfordUSA

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