Issue 421 (#422)

* fix undesired type promotion to Float64

* version bump

* typo

Author: jverzani

Project.toml

@@ -1,6 +1,6 @@
 name = "Roots"
 uuid = "f2b01f46-fcfa-551c-844a-d8ac1e96c665"
-version = "2.1.2"
+version = "2.1.3"
 
 [deps]
 ChainRulesCore = "d360d2e6-b24c-11e9-a2a3-2a2ae2dbcce4"

src/hybrid.jl

@@ -80,7 +80,7 @@ function solve!(
         r, a, b = state0.xn1, state.xn0, state.xn1
         Δr = abs(r - b)
         Δx = abs(b - a)
-        ts, TB = 1e-3, 1e2 # too small, too big
+        ts, TB = one(r)/1000, 100*one(r) # too small, too big
         if Δr >= TB * Δx
             adj = true
             r = b + sign(r - b) * TB * Δx  ## too big

test/test_find_zero.jl

@@ -36,6 +36,7 @@ struct Order3_Test <: Roots.AbstractSecantMethod end
         @test find_zero(sin, 3.0, m) ≈ pi
         @test find_zero(sin, big(3), m) ≈ pi
         @test find_zero(sin, big(3.0), m) ≈ pi
+        @test find_zero(x -> x^2 - 2.0f0, 2.0f0, m) ≈ sqrt(2) # issue 421
     end
 
     ## defaults for method argument