Introduce & and | for StoppingCriterion. (#56)

* Introduce & and | for StoppingCriterion.

* bump version.

Author: kellertuer

Project.toml

@@ -1,7 +1,7 @@
 name = "Manopt"
 uuid = "0fc0a36d-df90-57f3-8f93-d78a9fc72bb5"
 authors = ["Ronny Bergmann <manopt@ronnybergmann.net>"]
-version = "0.2.15"
+version = "0.2.16"
 
 [deps]
 ColorSchemes = "35d6a980-a343-548e-a6ea-1d62b119f2f4"

docs/src/solvers/index.md

@@ -47,6 +47,8 @@ Order = [:type]
 as well as the functions
 
 ```@docs
+Base.:&(::StoppingCriterion, ::StoppingCriterion)
+Base.:|(::StoppingCriterion, ::StoppingCriterion)
 get_reason
 get_stopping_criteria
 get_active_stopping_criteria

src/Manopt.jl

@@ -12,7 +12,7 @@ using Random: shuffle!
 using DataStructures: CircularBuffer, capacity, length, size, push!
 using StaticArrays
 import Random: rand, randperm
-import Base: copy, identity
+import Base: copy, identity, &, |
 import ManifoldsBase:
     ℝ,
     ℂ,
@@ -126,7 +126,7 @@ include("data/artificialDataFunctions.jl")
 
 include("random.jl")
 
-export ×, ^, ℝ, ℂ
+export ℝ, ℂ, &, |
 
 export Problem,
     ProximalProblem,

src/plans/stopping_criterion.jl

@@ -38,7 +38,7 @@ mutable struct StopAfterIteration <: StoppingCriterion
     reason::String
     StopAfterIteration(mIter::Int) = new(mIter, "")
 end
-function (c::StopAfterIteration)(p::P, o::O, i::Int) where {P<:Problem,O<:Options}
+function (c::StopAfterIteration)(::P, ::O, i::Int) where {P<:Problem,O<:Options}
     if i > c.maxIter
         c.reason = "The algorithm reached its maximal number of iterations ($(c.maxIter)).\n"
         return true
@@ -124,6 +124,33 @@ function (c::StopWhenAll)(p::P, o::O, i::Int) where {P<:Problem,O<:Options}
 end
 get_stopping_criteria(c::StopWhenAll) = c.criteria
 
+"""
+    &(s1,s2)
+    s1 & s2
+
+Combine two [`StoppingCriterion`](@ref) within an [`StopWhenAll`](@ref).
+If either `s1` (or `s2`) is already an [`StopWhenAll`](@ref), then `s2` (or `s1`) is
+appended to the list of [`StoppingCriterion`](@ref) within `s1` (or `s2`).
+
+# Example
+    a = StopAfterIteration(200) & StopWhenChangeLess(1e-6)
+    b = a & StopWhenGradientNormLess(1e-6)
+
+Is the same as
+
+    a = StopWhenAll(StopAfterIteration(200), StopWhenChangeLess(1e-6))
+    b = StopWhenAll(StopAfterIteration(200), StopWhenChangeLess(1e-6), StopWhenGradientNormLess(1e-6))
+"""
+function Base.:&(s1::S, s2::T) where {S<:StoppingCriterion,T<:StoppingCriterion}
+    return StopWhenAll(s1, s2)
+end
+function Base.:&(s1::S, s2::StopWhenAll) where {S<:StoppingCriterion}
+    return StopWhenAll(s1, s2.criteria...)
+end
+function Base.:&(s1::StopWhenAll, s2::T) where {T<:StoppingCriterion}
+    return StopWhenAll(s1.criteria..., s2)
+end
+
 @doc raw"""
     StopWhenAny <: StoppingCriterion
 
@@ -149,6 +176,34 @@ function (c::StopWhenAny)(p::P, o::O, i::Int) where {P<:Problem,O<:Options}
     return false
 end
 get_stopping_criteria(c::StopWhenAny) = c.criteria
+
+"""
+    |(s1,s2)
+    s1 | s2
+
+Combine two [`StoppingCriterion`](@ref) within an [`StopWhenAny`](@ref).
+If either `s1` (or `s2`) is already an [`StopWhenAny`](@ref), then `s2` (or `s1`) is
+appended to the list of [`StoppingCriterion`](@ref) within `s1` (or `s2`)
+
+# Example
+    a = StopAfterIteration(200) | StopWhenChangeLess(1e-6)
+    b = a | StopWhenGradientNormLess(1e-6)
+
+Is the same as
+
+    a = StopWhenAny(StopAfterIteration(200), StopWhenChangeLess(1e-6))
+    b = StopWhenAny(StopAfterIteration(200), StopWhenChangeLess(1e-6), StopWhenGradientNormLess(1e-6))
+"""
+function Base.:|(s1::S, s2::T) where {S<:StoppingCriterion,T<:StoppingCriterion}
+    return StopWhenAny(s1, s2)
+end
+function Base.:|(s1::S, s2::StopWhenAny) where {S<:StoppingCriterion}
+    return StopWhenAny(s1, s2.criteria...)
+end
+function Base.:|(s1::StopWhenAny, s2::T) where {T<:StoppingCriterion}
+    return StopWhenAny(s1.criteria..., s2)
+end
+
 """
     StopWhenCostLess <: StoppingCriterion
 

test/plans/test_stopping_criteria.jl

@@ -46,3 +46,17 @@ end
     @test s(p, o, 2) == true
     @test_throws ErrorException StopAfter(Second(-1))
 end
+
+@testset "Stopping Criterion &/| operators" begin
+    a = StopAfterIteration(200)
+    b = StopWhenChangeLess(1e-6)
+    c = StopWhenGradientNormLess(1e-6)
+    d = StopWhenAll(a, b, c)
+    @test typeof(d) === typeof(a & b & c)
+    @test typeof(d) === typeof(a & (b & c))
+    @test typeof(d) === typeof((a & b) & c)
+    e = StopWhenAny(a, b, c)
+    @test typeof(e) === typeof(a | b | c)
+    @test typeof(e) === typeof(a | (b | c))
+    @test typeof(e) === typeof((a | b) | c)
+end