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expmv vs. expv

Open acroy opened this issue 6 years ago • 3 comments

In Julia 1.0 the matrix exponential is done via exp and not expm as before. To have a consistent naming I would suggest to rename expmv and phimv.

acroy avatar Aug 12 '18 09:08 acroy

But then what is the v for without the m?

garrison avatar Aug 12 '18 13:08 garrison

Good question. To me, since exp computes the exponential of something, expv would give the exponential times a vector. But I don't know if that makes sense?

acroy avatar Aug 12 '18 16:08 acroy

In the original Expokit package https://www.maths.uq.edu.au/expokit/download.html

||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|||||||||||||||||||||||||||||||  MATLAB  |||||||||||||||||||||||||||||||
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chbv.m               Chebyshev algorithm for w = exp(t*A)v
padm.m               irreducible Pade algorithm for exp(t*A)
phiv.m               Krylov algorithm for w = exp(t*A)*v + t*phi(t*A)u
expv.m               Krylov algorithm for w = exp(t*A)*v
mexpv.m              Markov algorithm for w = exp(t*A)*v

A better reason for renaming could be that we follow the original convention.

pochoi avatar Aug 13 '18 08:08 pochoi