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ierfc(z) : sign definition - Gil - 11-20-2023 12:41 PM
Function ierfc(z)
Wolfram Alpha defines it as
z×erfc(z) - e^(-z²)/sqrt(pi)
and calculates accordingly.
At Wikipedia, French version,
of Function d'erreur, section "Extensions",
we find the reverse definition, ie:
e^(-z²)/sqrt(pi) - z×erfc(z).
Is there an "error" here?
What is the most common convention or the "correct" definition ?
Thanks for your answer.
RE: ierfc(z) : sign definition - Albert Chan - 11-20-2023 06:55 PM
(11-20-2023 12:41 PM)Gil Wrote: Function ierfc(z)
Wolfram Alpha defines it as
z×erfc(z) - e^(-z²)/sqrt(pi)
and calculates accordingly.
WA probably wrong, since their own Wollfram Mathworld site has the sign reveresd, see erfc1(x)