# Unexpected "="
**URL:** https://discourse.julialang.org/t/unexpected/14225
**Category:** General Usage
**Created:** [August 29, 2018, 2:44am UTC](https://discourse.julialang.org/t/unexpected/14225 "2018-08-29T02:44:03Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@microlifecc](https://discourse.julialang.org/u/microlifecc)
#### Post date: [August 29, 2018, 2:44am UTC](https://discourse.julialang.org/t/unexpected/14225/1 "2018-08-29T02:44:03Z")
This segment of Julia code filters keypoints in an image by an interpolation of the fields in the extremum from a difference of gaussian scale space.
```
mutable struct discrete_extremum
o
s
m
n
intensity
end
mutable struct candidateKeypoint
oE
s
m
n
σ
x
y
ω
end
LB = Array{candidateKeypoint}(0)
for extremum in LA′
for i = 1:5
H̄ = Hessian(extremum.o, extremum.s, extremum.m, extremum.n)
ḡ = ThreeDgradient(extremum.o, extremum.s, extremum.m, extremum.n)
α⋆ = alphaStar(H̄, ḡ)
ω = omega(H̄, ḡ, extremum.o, extremum.s, extremum.m, extremum.n)
δOE = δMin * 2^(extremum.o - 1)
α1⋆ = α⋆[1]
α2⋆ = α⋆[2]
α3⋆ = α⋆[3]
σ = (δOE/δMin) * σMin * 2^((α1⋆ + extremum.s)/nSpo)
x = δOE * (α2⋆ + extremum.m)
y = δOE * (α2⋆ + extremum.n)
extremum.s, extremum.m, extremum.n = round(Int64, extremum.s + α1⋆), round(Int64, extremum.m + α2⋆), round(Int64, extremum.n + α3⋆)
if max(abs(α1⋆), abs(α2⋆), abs(α3⋆)) < 0.6
break
end
end
if max(abs(α1⋆), abs(α2⋆), abs(α3⋆)) < 0.6
push!(LB, candidateKeypoint(extremum, σ, x, y, ω))
end
end
```
I am getting this error:
> syntax: unexpected “=”
in the part starting with LB =
There is no line number mentioned. Can you guys suggest what I am doing wrong?
---
### Author:  [@LeoK987](https://discourse.julialang.org/u/LeoK987)
#### Post date: [August 29, 2018, 2:47am UTC](https://discourse.julialang.org/t/unexpected/14225/2 "2018-08-29T02:47:25Z")
OK, sorry, I wasn’t concentrating enough, due to the special characters, I guess. Perhaps Julia behave in the same way? I have not used special characters in a code, so I can’t answer about it.
---
### Author:  [@microlifecc](https://discourse.julialang.org/u/microlifecc)
#### Post date: [August 29, 2018, 2:50am UTC](https://discourse.julialang.org/t/unexpected/14225/3 "2018-08-29T02:50:19Z")
Hi @LeoK987! Thanks for the help.
It’s just after the two structure definitions. Should I remove the special characters from variable names?
---
### Author:  [@quinnj](https://discourse.julialang.org/u/quinnj)
#### Post date: [August 29, 2018, 2:56am UTC](https://discourse.julialang.org/t/unexpected/14225/4 "2018-08-29T02:56:40Z")
You can just say:
```julia
LB = candidateKeypoint[]
```
Which initializes an empty `candidateKeypoint` Vector.
---
### Author:  [@jandehaan](https://discourse.julialang.org/u/jandehaan)
#### Post date: [August 29, 2018, 3:09am UTC](https://discourse.julialang.org/t/unexpected/14225/5 "2018-08-29T03:09:16Z")
It is not `LB =` that is giving you grief. Instead it is the ‘⋆’ character in the variables `α1⋆`, `α2⋆`, and `α3⋆`. I don’t know why.
---
### Author:  [@jandehaan](https://discourse.julialang.org/u/jandehaan)
#### Post date: [August 29, 2018, 3:17am UTC](https://discourse.julialang.org/t/unexpected/14225/6 "2018-08-29T03:17:59Z")
If you inspect line 28 in file [julia/julia-parser.scm at master · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/blob/master/src/julia-parser.scm) you’ll find that the ‘⋆’ character is defined as an operator with the same precedence as the ‘\*’ operator. That is why the Julia parser reports that the ‘=’ character is unexpected. It expects another operand.
---
### Author:  [@carstenbauer](https://discourse.julialang.org/u/carstenbauer)
#### Post date: [August 29, 2018, 4:10am UTC](https://discourse.julialang.org/t/unexpected/14225/7 "2018-08-29T04:10:34Z")
Please don’t double post, especially without cross referencing: [image processing - syntax: unexpected "=" in Julia - Stack Overflow](https://stackoverflow.com/questions/52068346/syntax-unexpected-in-julia/52069285#52069285)
---
### Author:  [@microlifecc](https://discourse.julialang.org/u/microlifecc)
#### Post date: [August 29, 2018, 4:15am UTC](https://discourse.julialang.org/t/unexpected/14225/8 "2018-08-29T04:15:21Z")
Oh sorry I forgot to put the reference! My bad!
---
### Author:  [@DNF](https://discourse.julialang.org/u/DNF)
#### Post date: [August 29, 2018, 6:27am UTC](https://discourse.julialang.org/t/unexpected/14225/9 "2018-08-29T06:27:52Z")
> [@microlifecc](#):
>
> `LB = Array{candidateKeypoint}(0)`
@quinnj already posted an alternative, but I expect this to fail, since `Array{candidateKeypoint}` is an abstract type.
Use `Array{.., 1}()` or `Vector{..}()` (in my view better), or, as suggested, `T[]`.
This is the reason I always prefer `Vector` and `Matrix` over `Array{ ..,1}` and `Array{..,2}`. More readable, and less likely to mistype.