# MethodError: no method matching -(::Int64, ::Array{Float64,1})

**URL:** <https://discourse.julialang.org/t/methoderror-no-method-matching-int64-array-float64-1/25806>\
**Category:** General Usage\
**Tags:** question\
**Created:** [June 28, 2019, 1:51pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-int64-array-float64-1/25806 "2019-06-28T13:51:28Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![aaron](https://avatars.discourse-cdn.com/v4/letter/a/e19adc/32.png) [@aaron](https://discourse.julialang.org/u/aaron)\
**Post date:** [June 28, 2019, 1:51pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-int64-array-float64-1/25806/1 "2019-06-28T13:51:28Z")

</div>

Hi, I am a newbie in Julia, using version 1.1.1.

MethodError: no method matching -(::Int64, ::Array{Float64,1})

What is wrong with the following code?

x1 = collect(0:0.1:2)  
x2a = 1-0.5_x1  
x2b = ifelse(2-2_x1.\>=0,2-2\*x1,0)

Thanks!

---

<div class="post-metadata">

**Author:** ![kristoffer.carlsson](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/kristoffer.carlsson/32/22_2.png) [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)\
**Post date:** [June 28, 2019, 1:52pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-int64-array-float64-1/25806/2 "2019-06-28T13:52:17Z")

</div>

`1` is an integer and `0.5x1` is a `Vector`. To do elementwise minus, do `1 .- 0.5x1` (or better `1 .- 0.5 .* x1`).

---

<div class="post-metadata">

**Author:** ![aaron](https://avatars.discourse-cdn.com/v4/letter/a/e19adc/32.png) [@aaron](https://discourse.julialang.org/u/aaron)\
**Post date:** [June 28, 2019, 1:57pm UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-int64-array-float64-1/25806/3 "2019-06-28T13:57:08Z")

</div>

Thank you!