# MethodError: no method matching isless(::Int64, ::Array{UnitRange{Int64},1})

**URL:** <https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970>\
**Category:** Optimization (Mathematical)\
**Created:** [January 26, 2021, 11:36am UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970 "2021-01-26T11:36:40Z")\
**Posts on this page:** 20\
**Page:** 1

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 26, 2021, 11:36am UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/1 "2021-01-26T11:36:40Z")

</div>

Hi I am a newbie to JuMP(Julia) and coding too,

I am currently computing the following constraints in code below however, it is returning the following error and I am not exactly sure how to solve and I do not understand the error at all. Some of the other constraints have been computed using similar syntax and are returning no errors. Is there something I am missing?

MethodError: no method matching isless(::Int64, ::Array{UnitRange{Int64},1})  
Closest candidates are:  
isless(!Matched::Missing, ::Any) at missing.jl:87  
isless(!Matched::FlexTable{1}, ::AbstractArray{T,1} where T) at C:\Users\glmab.julia\packages\TypedTables\ZF2b3\src\FlexTable.jl:308  
isless(::Real, !Matched::AbstractFloat) at operators.jl:166  
…

Stacktrace:  
[1] \<(::Int64, ::Array{UnitRange{Int64},1}) at .\operators.jl:277  
[2] \<=(::Int64, ::Array{UnitRange{Int64},1}) at .\operators.jl:326  
[3] macro expansion at C:\Users\glmab.julia\packages\MutableArithmetics\bPWR4\src\rewrite.jl:276 [inlined]  
[4] macro expansion at C:\Users\glmab.julia\packages\JuMP\qhoVb\src\macros.jl:440 [inlined]  
[5] (::var"#430#435")(::String) at C:\Users\glmab.julia\packages\JuMP\qhoVb\src\Containers\macro.jl:183  
[6] #28 at C:\Users\glmab.julia\packages\JuMP\qhoVb\src\Containers\container.jl:85 [inlined]  
[7] iterate at .\generator.jl:47 [inlined]  
[8] collect(::Base.Generator{JuMP.Containers.VectorizedProductIterator{Tuple{Array{String,1}}},JuMP.Containers.var"#28#29"{var"#430#435"}}) at .\array.jl:686  
[9] map(::Function, ::JuMP.Containers.VectorizedProductIterator{Tuple{Array{String,1}}}) at .\abstractarray.jl:2188  
[10] container(::Function, ::JuMP.Containers.VectorizedProductIterator{Tuple{Array{String,1}}}, ::Type{JuMP.Containers.DenseAxisArray}) at C:\Users\glmab.julia\packages\JuMP\qhoVb\src\Containers\container.jl:85  
[11] container(::Function, ::JuMP.Containers.VectorizedProductIterator{Tuple{Array{String,1}}}) at C:\Users\glmab.julia\packages\JuMP\qhoVb\src\Containers\container.jl:65  
[12] top-level scope at C:\Users\glmab.julia\packages\JuMP\qhoVb\src\macros.jl:91  
[13] top-level scope at In[54]:9  
[14] include\_string(::Function, ::Module, ::String, ::String) at .\loading.jl:1091

```julia
@constraints example2_netprofit begin
    tight1[j in j],
      sum(sum( (alpha[i]*w[i,n,np] + beta[i]*bs[i,n,np] ) for n in 1:length(n) if n <= np <= n+d) for i in Ij1) <= H

    tight2[j in j],
      sum(sum( (alpha[i]*w[i,n,np] + beta[i]*bs[i,n,np] ) for n in 1:length(n) if n <= np <= n+d) for i in Ij2) <= H

    tight3[j in j],
      sum(sum( (alpha[i]*w[i,n,np] + beta[i]*bs[i,n,np] ) for n in 1:length(n) if n <= np <= n+d) for i in Ij3) <= H

    tight4[j in j],
      sum(sum( (alpha[i]*w[i,n,np] + beta[i]*bs[i,n,np] ) for n in 1:length(n) if n <= np <= n+d) for i in Ij4) <= H

    tight5[j in j],
      sum(sum( (alpha[i]*w[i,n,np] + beta[i]*bs[i,n,np] ) for n in 1:length(n) if n <= np <= n+d) for i in Ij5) <= H

end

```

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 26, 2021, 12:52pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/2 "2021-01-26T12:52:03Z")

</div>

Hi, I would advise next time you post a MWE (Minimal Working Example) that reproduces your error as it is suggested in the item 3 of [this list of good practices](https://discourse.julialang.org/t/psa-make-it-easier-to-help-you/14757) when asking in this forum.

Only with the error message and this excerpt of code I would deduce that:

1. None of `alpha`, `w`, `beta`, and `bs` are JuMP variable containers. They all are `Number` `Vector`s because the message complains about the left-hand side of the `<=` being an `Int`.
2. `H` seems to be a `Vector` of `UnitRange{Int64}`, in other words something like this: `[1:10, 7:30, -10:10]` (a list of ranges).

Without a MWE we cannot know why your `Vector`s that seems as they should be JuMP variable containers are just `Number` containers, nor why `H` seem to be a `Vector` of ranges. Other confusing things are, for example: from where `np` comes from? should `np` be varying too or it is fixed?

---

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 26, 2021, 1:09pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/3 "2021-01-26T13:09:31Z")

</div>

Sorry I had forgotten to input the Set and Parameter information required, please see below

```julia
#Sets
# i 'tasks' /t1*t5/
# j 'units' /j1*j5/
# n 'events' /n0*n3/
# s 'states' /s1*s4/

i = ["t1","t2","t3","t4","t5"];
j = ["j1","j2","j3","j4","j5"];
n = [1:N]
s = ["s1","s2","s3","s4"]

#SubSets

#Ij1(i) 'tasks which can be performed in unit 1' /task1/
#Ij2(i) 'tasks which can be performed in unit 2' /task2/
#Ij3(i) 'tasks which can be performed in unit 3' /task3/
#Ij4(i) 'tasks which can be performed in unit 4' /task4/
#Ij5(i) 'tasks which can be performed in unit 5' /task5/

Ij1 = i[1];
Ij2 = i[2];
Ij3 = i[3];
Ij4 = i[4];
Ij5 = i[5];

#Is1(i)'tasks which process state 1 and either produce or consume' /task1,task2/
#Is2(i)'tasks which process state 2 and either produce or consume' /task1,task2,task3/
#Is3(i)'tasks which process state 3 and either produce or consume' /task3,task4,task5/
#Is4(i)'tasks which process state 4 and either produce or consume' /task4,task5/

Is1 = i[1:2];
Is2 = i[1:3];
Is3 = i[3:5];
Is4 = i[4:5];

#Ips1(i) 'tasks which produce state 2' //
#Ips2(i) 'tasks which produce state 2' /task1,task2/
#Ips3(i) 'tasks which produce state 3' /task3/
#Ips4(i) 'tasks which produce state 4' /task4,task5/

Ips1 = [];
Ips2 = i[1:2];
Ips3 = i[3];
Ips4 = i[4:5];

#Ics1(i) 'tasks which consume state 1' /task1,task2/
#Ics2(i) 'tasks which consume state 2' /task3/
#Ics3(i) 'tasks which consume state 3' /task4,task5/
#Ics4(i) 'tasks which consume state 4' //

Ics1 = i[1:2];
Ics2 = i[3];
Ics3 = i[4:5];
Ics4 = [];

Sr =s[1]
Sfis = s[2:3]
Sp = s[4]

#alias(i,ip)
#alias(j,jp)
#alias(n,np,npp)

ip = i;
jp = j;
np = n;
npp = n;

println(1:length(s))

```

AND

```julia
#PARAMETERS
#bmin = [0,0,0,0,0]

bmin = OrderedDict(
   "t1" => 0,
   "t2" => 0,
   "t3" => 0,
   "t4" => 0,
   "t5" => 0   
)

#bmax = [100,150,200,150,150]
bmax = OrderedDict(
   "t1" => 100,
   "t2" => 150,
   "t3" => 200,
   "t4" => 150,
   "t5" => 150 
)

#STin = [10000, 0, 0, 0]
STin = OrderedDict(
     "s1" => 10000,
     "s2" => 0,
     "s3" => 0,
     "s4" => 0)

#STmax = [+inf, 200, 250, +inf]
STmax = OrderedDict(
     "s1" => Inf,
     "s2" => 200,
     "s3" => 250,
     "s4" => 0
)

#alpha = [1.333, 1.333, 1.000, 0.667, 0.667]
alpha = OrderedDict(
"t1" => 1.333,
"t2" => 1.333,
"t3" => 1.000,
"t4" => 0.667,
"t5" => 0.667
)

#beta = [0.01333, 0.01333, 0.00500, 0.00445, 0.00445]
beta = OrderedDict(
"t1" => 0.01333,
"t2" => 0.01333,
"t3" => 0.00500,
"t4" => 0.00445,
"t5" => 0.00445       
)

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

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

#rho_table = wsv"""
#i s1 s2 s3 s4
#t1 -1 +1 0 0
#t2 -1 +1 0 0
#t3 0 -1 +1 0
#t4 0 0 -1 +1
#t5 0 0 -1 +1
#"""

rho_table = DataFrame([(i = "t1", s1 = -1, s2 = +1, s3 = 0, s4 = 0 ),
                   (i = "t2", s1 = -1, s2 = +1, s3 = 0, s4 = 0 ),
                   (i = "t3", s1 = 0, s2 = -1, s3 = +1, s4 = 0 ),
                   (i = "t4", s1 = 0, s2 = 0, s3 = -1, s4 = +1 ),
                   (i = "t5", s1 = 0, s2 = 0, s3 = -1, s4 = +1 )]);

rho = OrderedDict( (r[:i],states) => r[Symbol(states)] for r in eachrow(rho_table), states in s);

```

Comments are just GAMS syntax as I am converting from GAMS to JuMP.

---

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 26, 2021, 1:10pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/4 "2021-01-26T13:10:22Z")

</div>

Hope the above helps in clarifying

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 26, 2021, 1:17pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/5 "2021-01-26T13:17:01Z")

</div>

I did not found the definition of `H`, or `w`, or `bs`.

---

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 26, 2021, 1:25pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/6 "2021-01-26T13:25:16Z")

</div>

Now I am certain everything is in. My apologies. I will definitely do better next time

```julia
H = 8;
d = 0;
N = 4;

@variables example2_netprofit begin
    w[i in i, n in n, np in np], Bin
    bs[i in i, n in n, np in np] >= 0
    ST0[s in s, n in n] >= 0
    ST[s in s, n in n] >= 0
    Ts[i in i, n in n] >= 0
    Tf[i in i,n in n] >= 0
    NetP
    MS
end

```

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 26, 2021, 2:03pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/7 "2021-01-26T14:03:42Z")

</div>

The next time I suggest you either put all of your code in [https://pastebin.com/](https://pastebin.com/), or try to make it minimal (the M of MWE). The code was yet impossible to run because it did not include the packages (no `using` keywords), and it did not define `example2_netprofit`. I have added the necessary packages and created a simple model called `example2_netprofit`, so I was finally able to reproduce your problem.

The problem seem to be the `n <= np <= n+d` bit. `n` is an `Int64` and `np` is `1:4` (a `UnitRange{Int64}`). What are you trying to achieve here? `n <= 1:4` should give what results for which values of `n`?

The reassembled code is [here](https://pastebin.com/NWb2d5Ez), for anyone that is interested in helping too.

---

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 26, 2021, 3:22pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/8 "2021-01-26T15:22:45Z")

</div>

This is the original constraint from the paper that I am trying to reproduce in Julia (did in GAMS).

 ![2021-01-26](https://global.discourse-cdn.com/julialang/original/3X/7/4/740e44eb2895b551b6871357a4d629ed60f9119d.png)

np is an alias of n that is used in the model. elements in n are is a time/event point (model is a scheduling problem) and it is needed that when indexing from both sets that np and n not be the same i.e when n = 1, np != 1 and so forth. Hope I am making sense.

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 26, 2021, 3:58pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/9 "2021-01-26T15:58:16Z")

</div>

> [@GraceMabele](#):
>
> it is needed that when indexing from both sets that np and n not be the same i.e when n = 1, np != 1 and so forth.

I think you are wrong about this point. Both `n` and `n'` are from set `N`, and the restriction imposed by `n <= n' <= n + Δn` means that `n'` will go from equal to `n` to equal to `n + Δn` so, in fact, you will have `n == n'` in the first term of the sum. Your `Δn` (that is `d` in the code) is zero, so `n` is not sometimes equal to `n'` but always equal to `n'` in fact (the inner sum has only one term).

However, I do not understand how you ended up with `np` as a range. In your code `np` is a global variable, when it is clear by this constraint that `np` should be an iterator (i.e., you should use a `for` clause to introduce it), as `n` and `i` are. There also other problems in your code, like how you are trying to use `j` (you are not subscribing anything with `j` and you probably should not have variables `Ij1`, `Ij2`, etc), and that your global `n` is not a range like you think it is (that `1:length(n)` will always be `1:1`), but one problem at a time. I think what you want is something more like:

```julia
sum(alpha[i] * w[i, n, np] + beta[i] * bs[i, n, np] for i in Ij1 for n in 1:length(n) for np in n:(n+d)) <= H

```

---

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 28, 2021, 11:34am UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/10 "2021-01-28T11:34:25Z")

</div>

Thank you for your assistance. It worked. The only issue is Ij1 only has one element and I have noticed that when the set has only 1 element (t1) the for loop does not work i.e. it splits it into t and 1 and then returns the error key ‘t’ not found. What can I do to overcome this has it is another error I am experiencing in the other constraints that I am computing.

---

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 28, 2021, 11:41am UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/11 "2021-01-28T11:41:20Z")

</div>

Regarding n not being a range, how do I make it a range from 1:N? As that is a vital part of the model. When I used the function range I obtained a similar error. I would like to have it as n1, n2 n3, n4 etc but I will be changing N moving forward.

In GAMS, I can create a set such as n0 \* n10 (11 time points) or n0 \* n5 (6 time points, n0, n1, n2, n3, n4, n5) how can I do the same thing in JuMP.

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 28, 2021, 1:21pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/12 "2021-01-28T13:21:27Z")

</div>

> [@GraceMabele](#):
>
> Ij1 only has one element and I have noticed that when the set has only 1 element (t1) the for loop does not work i.e. it splits it into t and 1 and then returns the error key ‘t’ not found

`Ij1` is not a set. It is a single `String` and therefore when you iterate it, you get each character. If you wanted it to be a collection (in special, a `Vector` like you defined `i`, `j`, `n` and `s` in the start) you should put it inside brackets (`Ij1 = [i[1]]`). Now, this makes absolutely no sense to me. Why have a variable `Ij1` when you can just do `i[1]` instead? Why are you creating such variables with numbers at the end instead just accessing them from the `Vector`s when necessary? You will not be able to create loops using these variables (because the index is in the name), but you are able to create loops using `Vector`s.

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 28, 2021, 1:29pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/13 "2021-01-28T13:29:26Z")

</div>

> [@GraceMabele](#):
>
> In GAMS, I can create a set such as n0 \* n10 (11 time points) or n0 \* n5 (6 time points, n0, n1, n2, n3, n4, n5) how can I do the same thing in JuMP.

I am not sure if I understand your question. Julia ranges are created with `:` If you write `1:10` you have the range of numbers between `1` and `10` including both extremities. I do not understand why you are putting letters in front of the numbers, or trying to have them as variables.

> [@GraceMabele](#):
>
> Regarding n not being a range, how do I make it a range from 1:N?

I am not sure if you want `n` to be a range, do you not want it to be a number? An iterator that varies within `1:N`? About increasing a range, if you declare `r = 1:N` and `N` is `10`, when you change `N` to be `15`, for example, you should recompute `r = 1:N`.

---

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**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 29, 2021, 6:55am UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/14 "2021-01-29T06:55:56Z")

</div>

No it is a mis understanding but I have managed to fix the error as you directed prior. Thank you

---

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 29, 2021, 1:06pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/15 "2021-01-29T13:06:09Z")

</div>

Hi Henrique,

Thank so much for your previous assistance I have managed to compute all the constraints for this model. I am currently having problems with the objective function that is returning a key error.

```julia
@objective example2_netprofit Max begin
    NetP == sum(price[s] * sum(ST[s,n] + sum(rho[i,s]*bs[i,np,n] for i in 1:length(Ips4) for np in (n-d):n ) for n in 1:length(n) if n != 1:length(n)-1) for s in Sp)   
end

```

Here is the error returned

KeyError: key (1, “s4”) not found

Stacktrace:  
[1] getindex at C:\Users\glmab.julia\packages\OrderedCollections\DqfZ7\src\ordered\_dict.jl:346 [inlined]  
[2] getindex(::OrderedDict{Tuple{String,String},Int64}, ::Int64, ::String) at .\abstractdict.jl:499  
[3] (::var"#435#441"{Int64,Int64,String})(::Int64) at .\none:0  
[4] MappingRF at .\reduce.jl:93 [inlined]  
[5] \_foldl\_impl(::Base.MappingRF{var"#435#441"{Int64,Int64,String},Base.BottomRF{typeof(Base.add\_sum)}}, ::Base.\_InitialValue, ::UnitRange{Int64}) at .\reduce.jl:58  
[6] FlatteningRF at .\reduce.jl:119 [inlined]  
[7] MappingRF at .\reduce.jl:93 [inlined]  
[8] \_foldl\_impl(::Base.MappingRF{var"#436#440"{Int64,String},Base.FlatteningRF{Base.BottomRF{typeof(Base.add\_sum)}}}, ::Base.\_InitialValue, ::UnitRange{Int64}) at .\reduce.jl:58  
[9] foldl\_impl at .\reduce.jl:48 [inlined]  
[10] mapfoldl\_impl at .\reduce.jl:44 [inlined]  
[11] #mapfoldl#204 at .\reduce.jl:160 [inlined]  
[12] mapfoldl at .\reduce.jl:160 [inlined]  
[13] #mapreduce#208 at .\reduce.jl:287 [inlined]  
[14] mapreduce at .\reduce.jl:287 [inlined]  
[15] sum at .\reduce.jl:494 [inlined]  
[16] sum(::Base.Iterators.Flatten{Base.Generator{UnitRange{Int64},var"#436#440"{Int64,String}}}) at .\reduce.jl:511  
[17] (::var"#434#439"{String})(::Int64) at .\none:0  
[18] MappingRF at .\reduce.jl:93 [inlined]  
[19] FilteringRF at .\reduce.jl:105 [inlined]  
[20] \_foldl\_impl(::Base.FilteringRF{var"#437#442",Base.MappingRF{var"#434#439"{String},Base.BottomRF{typeof(Base.add\_sum)}}}, ::Base.\_InitialValue, ::UnitRange{Int64}) at .\reduce.jl:58  
[21] foldl\_impl at .\reduce.jl:48 [inlined]  
[22] mapfoldl\_impl at .\reduce.jl:44 [inlined]  
[23] #mapfoldl#204 at .\reduce.jl:160 [inlined]  
[24] mapfoldl at .\reduce.jl:160 [inlined]  
[25] #mapreduce#208 at .\reduce.jl:287 [inlined]  
[26] mapreduce at .\reduce.jl:287 [inlined]  
[27] sum at .\reduce.jl:494 [inlined]  
[28] sum(::Base.Generator{Base.Iterators.Filter{var"#437#442",UnitRange{Int64}},var"#434#439"{String}}) at .\reduce.jl:511  
[29] (::var"#433#438")(::String) at .\none:0  
[30] MappingRF at .\reduce.jl:93 [inlined]  
[31] \_foldl\_impl(::Base.MappingRF{var"#433#438",Base.BottomRF{typeof(Base.add\_sum)}}, ::Base.\_InitialValue, ::Array{String,1}) at .\reduce.jl:58  
[32] foldl\_impl at .\reduce.jl:48 [inlined]  
[33] mapfoldl\_impl(::typeof(identity), ::typeof(Base.add\_sum), ::NamedTuple{(),Tuple{}}, ::Base.Generator{Array{String,1},var"#433#438"}) at .\reduce.jl:44  
[34] mapfoldl(::Function, ::Function, ::Base.Generator{Array{String,1},var"#433#438"}; kw::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}) at .\reduce.jl:160  
[35] mapfoldl at .\reduce.jl:160 [inlined]  
[36] mapreduce(::Function, ::Function, ::Base.Generator{Array{String,1},var"#433#438"}; kw::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}) at .\reduce.jl:287  
[37] mapreduce at .\reduce.jl:287 [inlined]  
[38] sum at .\reduce.jl:494 [inlined]  
[39] sum(::Base.Generator{Array{String,1},var"#433#438"}) at .\reduce.jl:511  
[40] top-level scope at In[33]:4  
[41] top-level scope at C:\Users\glmab.julia\packages\MutableArithmetics\bPWR4\src\rewrite.jl:276  
[42] top-level scope at C:\Users\glmab.julia\packages\JuMP\y5vgk\src\macros.jl:928  
[43] top-level scope at In[33]:3  
[44] include\_string(::Function, ::Module, ::String, ::String) at .\loading.jl:1091

When I change the one component giving therror to for i in Ips4 see code below

```julia
@objective example2_netprofit Max begin
    NetP == sum(price[s] * sum(ST[s,n] + sum(rho[i,s]*bs[i,np,n] for i in Ips4 for np in (n-d):n ) for n in 1:length(n) if n != 1:length(n)-1) for s in Sp)   
end

```

It returns the following error

KeyError: key ([“t4”, “t5”], “s4”) not found

Stacktrace:  
[1] getindex at C:\Users\glmab.julia\packages\OrderedCollections\DqfZ7\src\ordered\_dict.jl:346 [inlined]  
[2] getindex(::OrderedDict{Tuple{String,String},Int64}, ::Array{String,1}, ::String) at .\abstractdict.jl:499  
[3] (::var"#445#451"{Array{String,1},Int64,String})(::Int64) at .\none:0  
[4] MappingRF at .\reduce.jl:93 [inlined]  
[5] \_foldl\_impl(::Base.MappingRF{var"#445#451"{Array{String,1},Int64,String},Base.BottomRF{typeof(Base.add\_sum)}}, ::Base.\_InitialValue, ::UnitRange{Int64}) at .\reduce.jl:58  
[6] FlatteningRF at .\reduce.jl:119 [inlined]  
[7] MappingRF at .\reduce.jl:93 [inlined]  
[8] \_foldl\_impl(::Base.MappingRF{var"#446#450"{Int64,String},Base.FlatteningRF{Base.BottomRF{typeof(Base.add\_sum)}}}, ::Base.\_InitialValue, ::Array{Array{String,1},1}) at .\reduce.jl:58  
[9] foldl\_impl at .\reduce.jl:48 [inlined]  
[10] mapfoldl\_impl at .\reduce.jl:44 [inlined]  
[11] #mapfoldl#204 at .\reduce.jl:160 [inlined]  
[12] mapfoldl at .\reduce.jl:160 [inlined]  
[13] #mapreduce#208 at .\reduce.jl:287 [inlined]  
[14] mapreduce at .\reduce.jl:287 [inlined]  
[15] sum at .\reduce.jl:494 [inlined]  
[16] sum(::Base.Iterators.Flatten{Base.Generator{Array{Array{String,1},1},var"#446#450"{Int64,String}}}) at .\reduce.jl:511  
[17] (::var"#444#449"{String})(::Int64) at .\none:0  
[18] MappingRF at .\reduce.jl:93 [inlined]  
[19] FilteringRF at .\reduce.jl:105 [inlined]  
[20] \_foldl\_impl(::Base.FilteringRF{var"#447#452",Base.MappingRF{var"#444#449"{String},Base.BottomRF{typeof(Base.add\_sum)}}}, ::Base.\_InitialValue, ::UnitRange{Int64}) at .\reduce.jl:58  
[21] foldl\_impl at .\reduce.jl:48 [inlined]  
[22] mapfoldl\_impl at .\reduce.jl:44 [inlined]  
[23] #mapfoldl#204 at .\reduce.jl:160 [inlined]  
[24] mapfoldl at .\reduce.jl:160 [inlined]  
[25] #mapreduce#208 at .\reduce.jl:287 [inlined]  
[26] mapreduce at .\reduce.jl:287 [inlined]  
[27] sum at .\reduce.jl:494 [inlined]  
[28] sum(::Base.Generator{Base.Iterators.Filter{var"#447#452",UnitRange{Int64}},var"#444#449"{String}}) at .\reduce.jl:511  
[29] (::var"#443#448")(::String) at .\none:0  
[30] MappingRF at .\reduce.jl:93 [inlined]  
[31] \_foldl\_impl(::Base.MappingRF{var"#443#448",Base.BottomRF{typeof(Base.add\_sum)}}, ::Base.\_InitialValue, ::Array{String,1}) at .\reduce.jl:58  
[32] foldl\_impl at .\reduce.jl:48 [inlined]  
[33] mapfoldl\_impl(::typeof(identity), ::typeof(Base.add\_sum), ::NamedTuple{(),Tuple{}}, ::Base.Generator{Array{String,1},var"#443#448"}) at .\reduce.jl:44  
[34] mapfoldl(::Function, ::Function, ::Base.Generator{Array{String,1},var"#443#448"}; kw::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}) at .\reduce.jl:160  
[35] mapfoldl at .\reduce.jl:160 [inlined]  
[36] mapreduce(::Function, ::Function, ::Base.Generator{Array{String,1},var"#443#448"}; kw::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}) at .\reduce.jl:287  
[37] mapreduce at .\reduce.jl:287 [inlined]  
[38] sum at .\reduce.jl:494 [inlined]  
[39] sum(::Base.Generator{Array{String,1},var"#443#448"}) at .\reduce.jl:511  
[40] top-level scope at In[34]:4  
[41] top-level scope at C:\Users\glmab.julia\packages\MutableArithmetics\bPWR4\src\rewrite.jl:276  
[42] top-level scope at C:\Users\glmab.julia\packages\JuMP\y5vgk\src\macros.jl:928  
[43] top-level scope at In[34]:3  
[44] include\_string(::Function, ::Module, ::String, ::String) at .\loading.jl:1091

I am looking for it to be indexed as (“t4”, “s4”) and (“t5”, “s4”)

Hope you can assist in this. The above information can be utilised.  
Thank you in advance

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 29, 2021, 1:33pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/16 "2021-01-29T13:33:41Z")

</div>

Can you post the formulation objective as you did with the previous constraint? (i.e., the mathematical formula)

Also,

1. You have `NetP == ...` in the objective, this makes little sense. The objective function is not a constraint, it should be just an expression (i.e., probably just the value you have in the right side of the `==`) not an equality.
2. `for n in 1:length(n) if n != 1:length(n)-1` this also makes little sense. First there is the terrible style of having an outer/global `n` that is used as limit for an inner/iterator/local `n`, you should give different names to your variables. But also `if n != 1:length(n)-1` is nonsense, `n` here is a value between `1` and `length(n)` (for the global `n`), it will always be different from a range.
3. In the code up until now you do not define a variable called `ST` (only `STmin` and `STmax`) and the you had in your old code `Sp` is probably not the `Sp` used here. So it is hard to know what is triggering the error, probably you have incorrect values in `Sp`.

---

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 29, 2021, 1:43pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/17 "2021-01-29T13:43:02Z")

</div>

Here is the mathematical formula

 ![2021-01-29](https://global.discourse-cdn.com/julialang/original/3X/c/5/c559356a0de170bbc6ae88811ffc9e803bc073dd.png)  
Point 1 noted  
Regarding point 2 n should be equal to the last element in n and that’s how I saw it best to compute it.  
Point 3, ST is a variable please see list of variables above (where bs[i,n,np] is etc)

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 29, 2021, 2:02pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/18 "2021-01-29T14:02:48Z")

</div>

In turn,

1. If `n` (the inner one) should only be the last element of `n` (the outer one) then just drop the `for n in 1:length(n) if n != 1:length(n)-1` (consequently, disappear with the inner `n`) and use `last(n)` in each place you would use `n` in the objective.
2. Sorry, I forgot to check the JuMP variable definitions, but this does not tell me what is `Sp`.

About the mathematical formulation, I have to say that, for me, the ∑ with `n = N` is irregular notation. If you say to me it means the last value in `N` I will believe you, but it seems kinda a sloppy way to do it. Ideally they should have graphed `n ∈ {max(N)}` (or something like that).

---

<div class="post-metadata">

**Author:** ![GraceMabele](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gracemabele/32/21360_2.png) [@GraceMabele](https://discourse.julialang.org/u/GraceMabele)\
**Post date:** [January 29, 2021, 2:18pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/20 "2021-01-29T14:18:21Z")

</div>

Sp is a set, Sp = [s[4]]

Defined amongst the sets  
Point 2 noted

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 29, 2021, 2:36pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970/21 "2021-01-29T14:36:04Z")

</div>

What is your `Ips4`? Because the problem appears when indexing `rho`, that is:

```julia
OrderedDict{Tuple{String, String}, Int64} with 20 entries:
  ("t1", "s1") => -1
  ("t2", "s1") => -1
  ("t3", "s1") => 0
...

```

So your change in the code to try to solve the problem is in the right direction, I think that if `Ips4` was

```julia
julia> Ips4
2-element Vector{String}:
 "t4"
 "t5"

```

as it should be, then **other** error (or no error) should have happened. Did you wrap `i[4:5]` in brackets? If so, remove them.

[Next page](https://discourse.julialang.org/t/methoderror-no-method-matching-isless-int64-array-unitrange-int64-1/53970.md?page=2)