lower bandwidth for Derivative(::Hermite) (#108)

* lower bandwidth for Derivative(::Hermite)

* bump version to v0.5.6

Author: jishnub

Project.toml

@@ -1,6 +1,6 @@
 name = "ApproxFunOrthogonalPolynomials"
 uuid = "b70543e2-c0d9-56b8-a290-0d4d6d4de211"
-version = "0.5.5"
+version = "0.5.6"
 
 [deps]
 AbstractFFTs = "621f4979-c628-5d54-868e-fcf4e3e8185c"

src/Spaces/Hermite/Hermite.jl

@@ -39,7 +39,7 @@ normalization(::Type{T}, sp::Hermite, k::Int) where T = (warn("This normalizatio
 Derivative(H::Hermite,order) = ConcreteDerivative(H,order)
 
 
-bandwidths(D::ConcreteDerivative{H}) where {H<:Hermite} = 0,D.order
+bandwidths(D::ConcreteDerivative{H}) where {H<:Hermite} = -D.order,D.order
 rangespace(D::ConcreteDerivative{H}) where {H<:Hermite} = domainspace(D)
 getindex(D::ConcreteDerivative{H},k::Integer,j::Integer) where {H<:Hermite} =
         j==k+D.order ? one(eltype(D))*2^D.order*pochhammer(k,D.order) : zero(eltype(D))