add solve for Order0, close #255 (#256)

* add solve for Order0

* version bump

Project.toml

@@ -1,6 +1,6 @@
 name = "Roots"
 uuid = "f2b01f46-fcfa-551c-844a-d8ac1e96c665"
-version = "1.3.5"
+version = "1.3.6"
 
 [deps]
 CommonSolve = "38540f10-b2f7-11e9-35d8-d573e4eb0ff2"
@@ -10,7 +10,7 @@ Setfield = "efcf1570-3423-57d1-acb7-fd33fddbac46"
 [compat]
 CommonSolve = "0.1, 0.2"
 Setfield = "0.7, 0.8"
-SpecialFunctions = "0.8, 0.9, 0.10, 1.0"
+SpecialFunctions = "0.8, 0.9, 0.10, 1"
 julia = "1.0"
 
 [extras]

src/find_zero.jl

@@ -971,5 +971,10 @@ function solve!(P::ZeroProblemIterator; verbose=false)
 end
 
 # thread verbose through
+"""
+    solve(𝐙::ZeroProblem, args...; verbose=false, kwargs...)
+
+Disptaches to `solve!(init(𝐙, args...; kwargs...))`. See [`solve!`](@ref) for details.
+"""
 CommonSolve.solve(F::ZeroProblem, args...; verbose=false, kwargs...) =
     solve!(init(F, args...; verbose=verbose, kwargs...); verbose=verbose)

src/order0.jl

@@ -59,6 +59,20 @@ function find_zero(
     return xstar
 end
 
+# give solve interface for Order0
+# XXX should creat iterator object for hybrid, rather than call out to
+# this version of find_zero...
+function solve!(𝐙::ZeroProblemIterator{<:Order0}; verbose=false)
+    F = 𝐙.F
+    M = Order1()
+    N = AlefeldPotraShi()
+    state = 𝐙.state
+    options = 𝐙.options
+    find_zero(M,N,F,
+              𝐙.state, 𝐙.options, 𝐙.logger, verbose)
+end
+
+
 # Robust version using some tricks: idea from algorithm described in
 # [The SOLVE button from the
 # HP-34]C(http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1979-12.pdf).

test/test_find_zero.jl

@@ -156,6 +156,7 @@ end
 
     # iterator interface (ZeroProblem, solve; init, solve!)
     meths = [
+        Order0(),
         Order1(),
         Roots.Order1B(),
         Roots.King(),