# TArray push in Turing.jl

**URL:** <https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980>\
**Category:** Probabilistic Programming\
**Created:** [May 22, 2020, 5:26pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980 "2020-05-22T17:26:57Z")\
**Posts on this page:** 10\
**Page:** 1

<div class="post-metadata">

**Author:** ![fooman](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/fooman/32/14883_2.png) [@fooman](https://discourse.julialang.org/u/fooman)\
**Post date:** [May 22, 2020, 5:26pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/1 "2020-05-22T17:26:57Z")

</div>

Just trying to convert the “Infinite Mixture” tutorial example to work with bivariate (as opposed to univariate) clusters: [https://turing.ml/dev/tutorials/6-infinitemixturemodel/](https://turing.ml/dev/tutorials/6-infinitemixturemodel/)

In the tutorial, one has:

```julia
    # Locations of the infinitely many clusters.
    μ = tzeros(Float64, 0)

```

and then applies push! as

```julia
# Create a new cluster?
        if z[i] > K
            push!(μ, 0.0)

```

I now have

```julia
   # bivariate case
   μ = tzeros(Float64, (0,2)) 
   ...  
   # Create a new cluster?
   if z[i] > K
      push!(μ, zeros(2)) 

```

I’m getting the following error:  
MethodError: no method matching push!(::Array{Float64,2}, ::Array{Float64,1})  
Closest candidates are:  
push!(::Any, ::Any, !Matched::Any) at abstractarray.jl:2158  
push!(::Any, ::Any, !Matched::Any, !Matched::Any…) at abstractarray.jl:2159  
push!(!Matched::Array{Any,1}, ::Any) at array.jl:920

What’s the correct syntax to use here?  
Thanks

---

<div class="post-metadata">

**Author:** ![cpfiffer](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/cpfiffer/32/208747_2.png) [@cpfiffer](https://discourse.julialang.org/u/cpfiffer)\
**Post date:** [May 23, 2020, 4:39pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/2 "2020-05-23T16:39:47Z")

</div>

Can you try something like

```julia
mu = TArray{TArray{Float64, 2}, 1}(undef, (0,2))

. . .
if z[i] > k
    push!(mu, tzeros(2))

```

No idea if this’ll work, can’t quite test it right now.

---

<div class="post-metadata">

**Author:** ![fooman](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/fooman/32/14883_2.png) [@fooman](https://discourse.julialang.org/u/fooman)\
**Post date:** [May 23, 2020, 5:05pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/3 "2020-05-23T17:05:26Z")

</div>

Doesn’t seem to work. I’m getting the following error message this time:

```julia
MethodError: no method matching TArray{TArray{Float64,2},1}(::UndefInitializer, ::Tuple{Int64,Int64})
Closest candidates are:
  TArray{TArray{Float64,2},1}(::Any, !Matched::Integer...) where {T, N} at C:\Users\.julia\packages\Libtask\Q1ugc\src\tarray.jl:36

```

FWIW, I’m using Turing.jl v0.12.0 and IJulia 1.21.2

Thnks

---

<div class="post-metadata">

**Author:** ![cpfiffer](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/cpfiffer/32/208747_2.png) [@cpfiffer](https://discourse.julialang.org/u/cpfiffer)\
**Post date:** [May 23, 2020, 5:41pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/4 "2020-05-23T17:41:31Z")

</div>

Try

```julia
mu = TArray{TArray{Float64, 1}, 1}(undef, 0)

if z[i] > K
    push!(mu, zeros(2)) 

```

---

<div class="post-metadata">

**Author:** ![fooman](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/fooman/32/14883_2.png) [@fooman](https://discourse.julialang.org/u/fooman)\
**Post date:** [May 23, 2020, 6:11pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/5 "2020-05-23T18:11:28Z")

</div>

Still doesn’t work.  
So with:

```julia
μ = TArray{TArray{Float64, 1}, 1}(undef, 0)
...
if z[i] > K
            push!(μ, zeros(2))

```

I get error:

```julia
MethodError: Cannot `convert` an object of type Array{Float64,1} to an object of type TArray{Float64,1}
Closest candidates are:
  convert(::Type{T}, !Matched::T) where T<:AbstractArray at abstractarray.jl:14
  convert(::Type{T}, !Matched::Factorization) where T<:AbstractArray at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.4\LinearAlgebra\src\factorization.jl:55
  convert(::Type{T}, !Matched::T) where T at essentials.jl:171

```

If I replace push! with push!(μ, tzeros(2))  
then the error message is:

```julia
MethodError: Cannot `convert` an object of type Float64 to an object of type TArray{Float64,1}
Closest candidates are:
  convert(::Type{T}, !Matched::T) where T<:AbstractArray at abstractarray.jl:14
  convert(::Type{T}, !Matched::Factorization) where T<:AbstractArray at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.4\LinearAlgebra\src\factorization.jl:55
  convert(::Type{T}, !Matched::T) where T at essentials.jl:171

```

---

<div class="post-metadata">

**Author:** ![cpfiffer](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/cpfiffer/32/208747_2.png) [@cpfiffer](https://discourse.julialang.org/u/cpfiffer)\
**Post date:** [May 23, 2020, 6:35pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/6 "2020-05-23T18:35:17Z")

</div>

Mistyped again. As indicated by the errors, this

```julia
push!(μ, zeros(2))

```

should be

```julia
push!(μ, tzeros(2))

```

---

<div class="post-metadata">

**Author:** ![fooman](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/fooman/32/14883_2.png) [@fooman](https://discourse.julialang.org/u/fooman)\
**Post date:** [May 23, 2020, 7:48pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/7 "2020-05-23T19:48:23Z")

</div>

Actually I tried that already, see the 2nd error message above. Still doesn’t work, mismatched type or something. Anything else to try?

---

<div class="post-metadata">

**Author:** ![mohamed82008](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mohamed82008/32/18171_2.png) [@mohamed82008](https://discourse.julialang.org/u/mohamed82008)\
**Post date:** [May 23, 2020, 9:13pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/8 "2020-05-23T21:13:39Z")

</div>

> [@cpfiffer](#):
>
> `push!(μ, tzeros(2))`

Works for me:

```julia
julia> μ = TArray{TArray{Float64, 1}, 1}(undef, 0);

julia> push!(μ, tzeros(2));

```

---

<div class="post-metadata">

**Author:** ![fooman](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/fooman/32/14883_2.png) [@fooman](https://discourse.julialang.org/u/fooman)\
**Post date:** [May 25, 2020, 2:09pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/9 "2020-05-25T14:09:20Z")

</div>

Ah yes. This seems to work actually.

So here’s the bivariate version of the model:

```julia
@model infiniteGMM(x) = begin 
    
    # Hyper-parameters, i.e. concentration parameter and parameters of H.
    α = 1.0
    μ0 = [0.0, 0.0]
    σ0 = 1.0
    
    # Define random measure, e.g. Dirichlet process.
    rpm = DirichletProcess(α)
    
    # Define the base distribution, i.e. expected value of the Dirichlet process.
    H = MvNormal(μ0, σ0)
    
    # Latent assignment.
    z = tzeros(Int, length(x))
        
    # Locations of the infinitely many clusters.
    μ = TArray{TArray{Float64, 1}, 1}(undef, 0);

    for i in 1:length(x)
        
        # Number of clusters.
        K = maximum(z)
        nk = Vector{Int}(map(k -> sum(z .== k), 1:K))

        # Draw the latent assignment.
        z[i] ~ ChineseRestaurantProcess(rpm, nk)
        
        # Create a new cluster?
        if z[i] > K
            push!(μ, tzeros(2))
            # Draw location of new cluster.
            μ[z[i]] ~ H
        end
                
        # Draw observation.
        x[i] ~ MvNormal(μ[z[i]], 1.0)
    end
end

```

If I try to sample from it:

```julia
model = infiniteGMM(x);
chains = sample(model, MH(), 10);

```

I get the following error:

```julia
MethodError: Cannot `convert` an object of type Array{Float64,1} to an object of type TArray{Float64,1}
Closest candidates are:
  convert(::Type{T}, !Matched::T) where T<:AbstractArray at abstractarray.jl:14
  convert(::Type{T}, !Matched::Factorization) where T<:AbstractArray at 

```

Any ideas where this is coming from? Looks like again some dimensional/indexing mismatch.  
I’m using a sample bivariate mixture as follows:

```julia
y1 = rand(MvNormal([1., 3.], 0.5), 250);
y2 = rand(MvNormal([-1., 0.], 0.5), 400);
x = reduce(hcat, [y1, y2])

```

Thanks

---

<div class="post-metadata">

**Author:** ![mohamed82008](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mohamed82008/32/18171_2.png) [@mohamed82008](https://discourse.julialang.org/u/mohamed82008)\
**Post date:** [May 25, 2020, 2:28pm UTC](https://discourse.julialang.org/t/tarray-push-in-turing-jl/39980/10 "2020-05-25T14:28:26Z")

</div>

Please open an issue.