Add setdiff for point

Author: dlfivefifty

Project.toml

@@ -31,7 +31,7 @@ ToeplitzMatrices = "c751599d-da0a-543b-9d20-d0a503d91d24"
 [compat]
 AbstractFFTs = "≥ 0.3.1"
 BandedMatrices = "0.9.0"
-BlockArrays = "0.8.0"
+BlockArrays = "0.8, 0.9"
 BlockBandedMatrices = "0.4.0"
 Calculus = "≥ 0.1.15"
 DSP = "≥ 0.5.1"

src/Domains/Domains.jl

@@ -46,6 +46,16 @@ affine_setdiff(d::Domain, ptsin::UnionDomain) =
 affine_setdiff(d::Domain, ptsin::WrappedDomain{<:AbstractVector}) = 
     _affine_setdiff(d, ptsin.domain)
 
+function _affine_setdiff(d::Domain, p::Number) 
+    isempty(d) && return d
+    p ∉ d  && return d
+    a,b = endpoints(d)
+    if leftendpoint(d) > rightendpoint(d) 
+        a,b = b,a
+    end
+    UnionDomain(a..p, p..b) # TODO: Clopen interval
+end
+
 function _affine_setdiff(d::Domain, pts)    
     isempty(pts) && return d
     tol=sqrt(eps(arclength(d)))