KeyError when indexing from an OrderedDict in for loop

General Usage
1

How can I access or index an OrderedDict?
I tried as below but returning keyerror

using DataStructures

price = OrderedDict(
"s1" => 0,
"s2" => 0,
"s3" => 0,
"s4" => 5
)

for s in 1:length(S)
    price[s]
end

Returns Error

KeyError: key 1 not found

Stacktrace:
[1] getindex(::OrderedDict{String,Int64}, ::Int64) at C:\Users\glmab.julia\packages\OrderedCollections\cP9uu\src\ordered_dict.jl:380
[2] top-level scope at .\In[22]:2
[3] include_string(::Function, ::Module, ::String, ::String) at .\loading.jl:1091

2

You still need to use they keys of the ordered dict, so iterate over s in keys(price)

3

The full equation is as follows

sum((price[s]*d[s,n]) for n in 1:length(N) for s in S  )

And it returns the error

KeyError: key 1 not found

Stacktrace:
[1] getindex at .\dict.jl:467 [inlined]
[2] lookup_index at C:\Users\glmab.julia\packages\JuMP\y5vgk\src\Containers\DenseAxisArray.jl:145 [inlined]
[3] _to_index_tuple at C:\Users\glmab.julia\packages\JuMP\y5vgk\src\Containers\DenseAxisArray.jl:154 [inlined] (repeats 2 times)
[4] to_index at C:\Users\glmab.julia\packages\JuMP\y5vgk\src\Containers\DenseAxisArray.jl:174 [inlined]
[5] getindex(::JuMP.Containers.DenseAxisArray{VariableRef,2,Tuple{Array{String,1},Array{UnitRange{Int64},1}},Tuple{Dict{String,Int64},Dict{UnitRange{Int64},Int64}}}, ::String, ::Int64) at C:\Users\glmab.julia\packages\JuMP\y5vgk\src\Containers\DenseAxisArray.jl:192
[6] (::var"#409#412"{Int64})(::String) at .\none:0
[7] MappingRF at .\reduce.jl:93 [inlined]
[8] _foldl_impl(::Base.MappingRF{var"#409#412"{Int64},Base.BottomRF{typeof(Base.add_sum)}}, ::Base._InitialValue, ::Base.KeySet{String,OrderedDict{String,Int64}}) at .\reduce.jl:58
[9] FlatteningRF at .\reduce.jl:119 [inlined]
[10] MappingRF at .\reduce.jl:93 [inlined]
[11] _foldl_impl(::Base.MappingRF{var"#410#411",Base.FlatteningRF{Base.BottomRF{typeof(Base.add_sum)}}}, ::Base._InitialValue, ::UnitRange{Int64}) at .\reduce.jl:58
[12] foldl_impl at .\reduce.jl:48 [inlined]
[13] mapfoldl_impl at .\reduce.jl:44 [inlined]
[14] #mapfoldl#204 at .\reduce.jl:160 [inlined]
[15] mapfoldl at .\reduce.jl:160 [inlined]
[16] #mapreduce#208 at .\reduce.jl:287 [inlined]
[17] mapreduce at .\reduce.jl:287 [inlined]
[18] sum at .\reduce.jl:494 [inlined]
[19] sum(::Base.Iterators.Flatten{Base.Generator{UnitRange{Int64},var"#410#411"}}) at .\reduce.jl:511
[20] top-level scope at In[25]:4
[21] include_string(::Function, ::Module, ::String, ::String) at .\loading.jl:1091

With S and N being

S = ["s1","s2","s3","s4"]
N = [1:10]

d is a variable

using JuMP

m = Model()

@variables m begin
  d[s in S, n in N] >= 0
end
4

I don’t know how JuMP macros work, but the basic problem is the same - an OrderedDict still has to be indexed by its keys, not by integers (unless you are using integers as keys, but in that case you might as well just use an array?)

julia> for s in keys(price)
           @show s, price[s]
       end
(s, price[s]) = ("s1", 0)
(s, price[s]) = ("s2", 0)
(s, price[s]) = ("s3", 0)
(s, price[s]) = ("s4", 5)