sethaxen / ExponentialAction.jl

Compute the action of the matrix exponential
MIT License
24 stars 0 forks source link

Potential typo #28

Closed colinfang closed 1 month ago

colinfang commented 5 months ago

In https://github.com/sethaxen/ExponentialAction.jl/blob/v0.2.8/src/parameters.jl#L54

Aᵖ⁺¹ = A * A
d = t_norm * sqrt(opnormest1(A))

Should A here be Aᵖ⁺¹ instead?

Because we are calculating the 1-norm for A^2 as in $d_p = \lVert A^p \rVert ^{1/p}$ for $p = 2$

sethaxen commented 5 months ago

Thanks for the issue! I'll need to make a detailed comparison with the paper to be sure, but this indeed looks like it could be a mistake. Would be nice to find a case where this yields inaccurate results.

sethaxen commented 1 month ago

Fixed by #29