Log-Linear Interpolation

General Usage
1

Does Interpolations have a log-linear model. Its common for interpolating interest rate curves.
e.g.

t               = 1:5
zero_rate       = .01:.01:.05
discount_factor = @. exp(- t * zero_rate)

log_linear      = exp ∘ interpolate( (x,), (t .* zero_rate), Gridded(Linear())) 

#or equivalently 

log_linear      = exp ∘ interpolate( (x,), - log.(discount_factor), Gridded(Linear()))
2

If you’re talking about the package Interpolations.jl it does not, but maybe look at