Add arithmetic for UnivariateFinite objects.

[ablaom]

edited

This PR implements +(::U, ::U), -(::U, ::U), -(::U), *(::U, ::Number), *(::Number, U), \(::U, ::Number) where U is a UnivariateFinite or UnivariateFiniteArray, with performant versions for the latter. These symbols are being given the usual meanings when we view a UnivariateFinite object as a finite measure. It seems the restriction to Number type is necessary to avoid ambiguity with Base.*(::Number, ::AbstractArray).

It also adds some doc-string fixes and a fix to allow show method to work when "probabilities" are complex, etc.

Resolves #10.

[codecov-commenter]

Codecov Report

Merging #12 (a73e225) into dev (076cbd2) will decrease coverage by 1.55%.
The diff coverage is 82.50%.

@@            Coverage Diff             @@
##              dev      #12      +/-   ##
==========================================
- Coverage   93.02%   91.47%   -1.56%     
==========================================
  Files           4        5       +1     
  Lines         373      387      +14     
==========================================
+ Hits          347      354       +7     
- Misses         26       33       +7     

Impacted Files	Coverage Δ
src/arrays.jl	98.88% <ø> (ø)
src/methods.jl	80.74% <0.00%> (-6.36%)	⬇️
src/types.jl	96.22% <ø> (ø)
src/arithmetic.jl	97.05% <97.05%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 076cbd2...a73e225. Read the comment docs.