diff --git a/src/args.jl b/src/args.jl
index 3694bd35..5d140738 100644
--- a/src/args.jl
+++ b/src/args.jl
@@ -983,7 +983,8 @@ convertLegendValue(v::AbstractArray) = map(convertLegendValue, v)
 # anything else is returned as-is
 function slice_arg(v::AMat, idx::Int)
     c = mod1(idx, size(v,2))
-    size(v,1) == 1 ? v[1,c] : v[:,c]
+    m,n = indices(v)
+    size(v,1) == 1 ? v[first(m),n[c]] : v[:,n[c]]
 end
 slice_arg(wrapper::InputWrapper, idx) = wrapper.obj
 slice_arg(v, idx) = v
diff --git a/src/axes.jl b/src/axes.jl
index 850b67cb..d2c165af 100644
--- a/src/axes.jl
+++ b/src/axes.jl
@@ -472,10 +472,10 @@ end
 
 # add the discrete value for each item.  return the continuous values and the indices
 function discrete_value!(axis::Axis, v::AMat)
-    n,m = size(v)
-    cmat = zeros(n,m)
-    discrete_indices = zeros(Int, n, m)
-    for i=1:n, j=1:m
+    n,m = indices(v)
+    cmat = zeros(v)
+    discrete_indices = similar(Array{Int}, n, m)
+    @inbounds for i=n, j=m
         cmat[i,j], discrete_indices[i,j] = discrete_value!(axis, v[i,j])
     end
     cmat, discrete_indices
diff --git a/src/backends/glvisualize.jl b/src/backends/glvisualize.jl
index d989b927..b122cda0 100644
--- a/src/backends/glvisualize.jl
+++ b/src/backends/glvisualize.jl
@@ -1291,8 +1291,8 @@ function gl_surface(x,y,z, kw_args)
         if isa(x, AbstractMatrix) && isa(y, AbstractMatrix)
             main = map(s->map(Float32, s), (x, y, z))
         elseif isa(x, AbstractVector) || isa(y, AbstractVector)
-            x = Float32[x[i] for i = 1:size(z,1), j = 1:size(z,2)]
-            y = Float32[y[j] for i = 1:size(z,1), j = 1:size(z,2)]
+            x = Float32[x[i] for i = indices(z,1), j = indices(z,2)]
+            y = Float32[y[j] for i = indices(z,1), j = indices(z,2)]
             main = (x, y, map(Float32, z))
         else
             error("surface: combination of types not supported: $(typeof(x)) $(typeof(y)) $(typeof(z))")
@@ -1301,7 +1301,7 @@ function gl_surface(x,y,z, kw_args)
             points = map(Point3f0, zip(vec(x), vec(y), vec(z)))
             faces = Cuint[]
             idx = (i,j) -> sub2ind(size(z), i, j) - 1
-            for i=1:size(z,1), j=1:size(z,2)
+            for i=indices(z,1), j=indices(z,2)
 
                 i < size(z,1) && push!(faces, idx(i, j), idx(i+1, j))
                 j < size(z,2) && push!(faces, idx(i, j), idx(i, j+1))