# Cannot specify symbolic types

**URL:** https://discourse.julialang.org/t/cannot-specify-symbolic-types/65702
**Category:** Modelling & Simulations
**Tags:** symbolic, symbolics
**Created:** [August 2, 2021, 10:15pm UTC](https://discourse.julialang.org/t/cannot-specify-symbolic-types/65702 "2021-08-02T22:15:45Z")
**Posts on this page:** 3
**Page:** 1

<div class="post-metadata">

### Author: ![yuvalw](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/yuvalw/32/19224_2.png) [@yuvalw](https://discourse.julialang.org/u/yuvalw)
#### Post date: [August 2, 2021, 10:15pm UTC](https://discourse.julialang.org/t/cannot-specify-symbolic-types/65702/1 "2021-08-02T22:15:45Z")

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Hello,  
I cannot specify any symbolic type.

```julia
using Symbolics
@variables u::Complex # or any other type

```

gives the following error:

```julia
ERROR: LoadError: AssertionError: @variables expects a tuple of expressions or an expression of a tuple (`@variables x y z(t) v[1:3] w[1:2,1:4]` or `@variables x y z(t) v[1:3] w[1:2,1:4] k=1.0`)

```

Thanks for any help.

---

<div class="post-metadata">

### Author: ![contradict](https://avatars.discourse-cdn.com/v4/letter/c/ac91a4/32.png) [@contradict](https://discourse.julialang.org/u/contradict)
#### Post date: [August 3, 2021, 4:57pm UTC](https://discourse.julialang.org/t/cannot-specify-symbolic-types/65702/3 "2021-08-03T16:57:05Z")

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Seems to work for me, what version of Symbolics do you have installed?

```julia
julia> @variables x::Real z::Complex{Real} (X::Real)[1:10, 1:10] (Z::Complex{Real})[1:10] s::String
5-element Vector{Any}:
 x
 z
  X[1:10,1:10]
  Z[1:10]
  s

(jl_hqZDlM) pkg> st
      Status `/tmp/jl_hqZDlM/Project.toml`
  [0c5d862f] Symbolics v1.4.2

```

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<div class="post-metadata">

### Author: ![aramirezreyes](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/aramirezreyes/32/42573_2.png) [@aramirezreyes](https://discourse.julialang.org/u/aramirezreyes)
#### Post date: [August 3, 2021, 5:42pm UTC](https://discourse.julialang.org/t/cannot-specify-symbolic-types/65702/4 "2021-08-03T17:42:28Z")

</div>

From [this issue](https://github.com/JuliaSymbolics/Symbolics.jl/issues/270) support for Complex was just merged 14 days ago so yes, it is probably that you are using an older version.