use pairs in findmin and findmax, supporting all indexable coll…

…ections

base/array.jl

@@ -2068,12 +2068,12 @@ function findmax(a)
     if isempty(a)
         throw(ArgumentError("collection must be non-empty"))
     end
-    s = start(a)
-    mi = i = 1
-    m, s = next(a, s)
-    while !done(a, s)
-        ai, s = next(a, s)
-        i += 1
+    p = pairs(a)
+    s = start(p)
+    (mi, m), s = next(p, s)
+    i = mi
+    while !done(p, s)
+        (i, ai), s = next(p, s)
         ai != ai && continue # assume x != x => x is a NaN
         if m != m || isless(m, ai)
             m = ai
@@ -2108,12 +2108,12 @@ function findmin(a)
     if isempty(a)
         throw(ArgumentError("collection must be non-empty"))
     end
-    s = start(a)
-    mi = i = 1
-    m, s = next(a, s)
-    while !done(a, s)
-        ai, s = next(a, s)
-        i += 1
+    p = pairs(a)
+    s = start(p)
+    (mi, m), s = next(p, s)
+    i = mi
+    while !done(p, s)
+        (i, ai), s = next(p, s)
         ai != ai && continue
         if m != m || isless(ai, m)
             m = ai

base/sparse/sparsematrix.jl

@@ -1905,8 +1905,8 @@ end
 
 findmin(A::SparseMatrixCSC{Tv,Ti}, region) where {Tv,Ti} = @_findr(<, A, region, Tv, Ti)
 findmax(A::SparseMatrixCSC{Tv,Ti}, region) where {Tv,Ti} = @_findr(>, A, region, Tv, Ti)
-findmin(A::SparseMatrixCSC) = (r=findmin(A,(1,2)); (r[1][1], r[2][1]))
-findmax(A::SparseMatrixCSC) = (r=findmax(A,(1,2)); (r[1][1], r[2][1]))
+findmin(A::SparseMatrixCSC) = (r=findmin(A,(1,2)); (r[1][1], CartesianIndex(ind2sub(A, r[2][1]))))
+findmax(A::SparseMatrixCSC) = (r=findmax(A,(1,2)); (r[1][1], CartesianIndex(ind2sub(A, r[2][1]))))
 
 indmin(A::SparseMatrixCSC) = findmin(A)[2]
 indmax(A::SparseMatrixCSC) = findmax(A)[2]

test/arrayops.jl

@@ -497,7 +497,7 @@ end
     @test indmin(5:-2:1) == 3
 
     #23094
-    @test findmax(Set(["abc"])) === ("abc", 1)
+    @test_throws MethodError findmax(Set(["abc"]))
     @test findmin(["abc", "a"]) === ("a", 2)
     @test_throws MethodError findmax([Set([1]), Set([2])])
     @test findmin([0.0, -0.0]) === (-0.0, 2)
@@ -1811,6 +1811,11 @@ s, si = findmax(S)
 @test a == b == s
 @test ai == bi == si
 
+for X in (A, B, S)
+    @test findmin(X) == findmin(Dict(pairs(X)))
+    @test findmax(X) == findmax(Dict(pairs(X)))
+end
+
 fill!(B, 2)
 @test all(x->x==2, B)
 

test/sparse/sparse.jl

@@ -992,8 +992,8 @@ end
 
     S = spzeros(10,8)
     A = Array(S)
-    @test indmax(S) == indmax(A) == 1
-    @test indmin(S) == indmin(A) == 1
+    @test indmax(S) == indmax(A) == CartesianIndex(1,1)
+    @test indmin(S) == indmin(A) == CartesianIndex(1,1)
 
     A = Array{Int}(0,0)
     S = sparse(A)