Makie Axis xticks: passing (datetimes, labels) fails with MethodError

lfenzo · December 7, 2025, 2:08pm

Hello!

I’m trying to change the DateTime xtick label intervals in my Makie plot by manually passing the xticks parameter to Axis as a tuple with two vectors: (datetimes, labels). According to the current xticks docs:

The following is a list of common tick objects.

Numeric:

A vector of numbers

(…)

DateTime:

A vector of DateTimes

A tuple with two vectors (datetimes, labels)

DateTimeTicks, the default tick finder for datetime ticks

However, with this MWE

using CairoMakie
fig = Figure()
x = DateTime(2025, 1, 1):Day(1):DateTime(2025, 1, 10) 
ax = Axis(fig[1, 1], xticks=(x, string.(x)))
lines!(ax, x, rand(10))

I get:

MethodError: Cannot `convert` an object of type DateTime to an object of type Float64
The function `convert` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  convert(::Type{T}, ::IntervalArithmetic.ExactReal) where T<:Real
   @ IntervalArithmetic ~/.julia/packages/IntervalArithmetic/55mUT/src/intervals/exact_literals.jl:130
  convert(::Type{T}, ::Unitful.Quantity) where T<:Real
   @ Unitful ~/.julia/packages/Unitful/pKTDo/src/conversion.jl:167
  convert(::Type{T}, ::Unitful.Level) where T<:Real
   @ Unitful ~/.julia/packages/Unitful/pKTDo/src/logarithm.jl:46
  ...

Any idea of what I am missing here?

Thanks in advance!

Environment Packages

  [13f3f980] CairoMakie v0.15.8
  [a93c6f00] DataFrames v1.8.1
  [7073ff75] IJulia v1.33.0
  [945b72a4] MarketData v0.15.1

Full Stacktrace

MethodError: Cannot `convert` an object of type Date to an object of type Float64
The function `convert` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  convert(::Type{T}, ::IntervalArithmetic.ExactReal) where T<:Real
   @ IntervalArithmetic ~/.julia/packages/IntervalArithmetic/55mUT/src/intervals/exact_literals.jl:130
  convert(::Type{T}, ::Unitful.Quantity) where T<:Real
   @ Unitful ~/.julia/packages/Unitful/pKTDo/src/conversion.jl:167
  convert(::Type{T}, ::Unitful.Level) where T<:Real
   @ Unitful ~/.julia/packages/Unitful/pKTDo/src/logarithm.jl:46
  ...


Stacktrace:
  [1] setindex!
    @ ./genericmemory.jl:259 [inlined]
  [2] unsafe_copyto!(dest::Memory{Float64}, doffs::Int64, src::Memory{Date}, soffs::Int64, n::Int64)
    @ Base ./genericmemory.jl:158
  [3] unsafe_copyto!
    @ ./genericmemory.jl:137 [inlined]
  [4] _copyto_impl!
    @ ./array.jl:308 [inlined]
  [5] copyto!
    @ ./array.jl:294 [inlined]
  [6] copyto!
    @ ./array.jl:319 [inlined]
  [7] copyto_axcheck!
    @ ./abstractarray.jl:1176 [inlined]
  [8] Array
    @ ./array.jl:621 [inlined]
  [9] convert
    @ ./array.jl:614 [inlined]
 [10] get_tickvalues
    @ ~/.julia/packages/Makie/Vn16E/src/makielayout/lineaxis.jl:678 [inlined]
 [11] get_tickvalues
    @ ~/.julia/packages/Makie/Vn16E/src/makielayout/lineaxis.jl:610 [inlined]
 [12] get_ticks
    @ ~/.julia/packages/Makie/Vn16E/src/makielayout/lineaxis.jl:598 [inlined]
 [13] get_ticks(::Nothing, ticks::Vector{Date}, scale::Function, formatter::Makie.Automatic, vmin::Float64, vmax::Float64)
    @ Makie ~/.julia/packages/Makie/Vn16E/src/dim-converts/dim-converts.jl:77
 [14] (::Makie.var"#LineAxis##22#LineAxis##23"{Observable{Any}})(::Tuple{Float32, Tuple{Float32, Float32}, Bool}, ::Nothing, limits::Tuple{Float64, Float64}, ticks::Vector{Date}, tickformat::Makie.Automatic, scale::Function)
    @ Makie ~/.julia/packages/Makie/Vn16E/src/makielayout/lineaxis.jl:449
 [15] (::Observables.MapCallback)(value::Any)
    @ Observables ~/.julia/packages/Observables/YdEbO/src/Observables.jl:436
 [16] #map!#298
    @ ~/.julia/packages/Makie/Vn16E/src/scenes.jl:191 [inlined]
 [17] map!
    @ ~/.julia/packages/Makie/Vn16E/src/scenes.jl:181 [inlined]
 [18] Makie.LineAxis(parent::Scene, attrs::Attributes)
    @ Makie ~/.julia/packages/Makie/Vn16E/src/makielayout/lineaxis.jl:445
 [19] Makie.LineAxis(parent::Scene; kwargs...)
    @ Makie ~/.julia/packages/Makie/Vn16E/src/makielayout/lineaxis.jl:8
 [20] LineAxis
    @ ~/.julia/packages/Makie/Vn16E/src/makielayout/lineaxis.jl:6 [inlined]
 [21] initialize_block!(ax::Axis; palette::Nothing)
    @ Makie ~/.julia/packages/Makie/Vn16E/src/makielayout/blocks/axis.jl:346
 [22] initialize_block!(ax::Axis)
    @ Makie ~/.julia/packages/Makie/Vn16E/src/makielayout/blocks/axis.jl:154
 [23] _block(T::Type{Axis}, fig_or_scene::Figure, args::Vector{Any}, kwdict::Dict{Symbol, Any}, bbox::Nothing; kwdict_complete::Bool)
    @ Makie ~/.julia/packages/Makie/Vn16E/src/makielayout/blocks.jl:405
 [24] _block
    @ ~/.julia/packages/Makie/Vn16E/src/makielayout/blocks.jl:321 [inlined]
 [25] #_block#1538
    @ ~/.julia/packages/Makie/Vn16E/src/makielayout/blocks.jl:266 [inlined]
 [26] _block(::Type{Axis}, ::GridPosition; kwargs::@Kwargs{xticks::Vector{Date}, yticks::UnitRange{Int64}, ylabel::String})
    @ Makie ~/.julia/packages/Makie/Vn16E/src/makielayout/blocks.jl:260
 [27] _block
    @ ~/.julia/packages/Makie/Vn16E/src/makielayout/blocks.jl:251 [inlined]
 [28] #_#1536
    @ ~/.julia/packages/Makie/Vn16E/src/makielayout/blocks.jl:242 [inlined]
 [29] top-level scope
    @ In[39]:8
 [30] eval(m::Module, e::Any)

jules · December 7, 2025, 3:33pm

Yeah, the problem is that Makie tries to use the float axis tick logic on your tick object, because at this point it doesn’t yet know you’re trying to use a datetime axis. You could plot the lines first (then the Axis has changed to datetime mode) and then set the ticks.

technocrat · December 7, 2025, 11:59pm

When dealing with equal interval dates like this, a workaround is to space the ticks with integers and label them with strings converted from the date objects

using CairoMakie
using Dates

# Date values only used to build labels
dates = DateTime(2025, 1, 1):Day(1):DateTime(2025, 1, 10)
labels = Dates.format.(dates, "yyyy-mm-dd")

x = 1:10
y = rand(10)

fig = Figure()
ax = Axis(fig[1, 1])

# ticks are numeric, labels are strings
ax.xticks[] = (collect(x), labels)
ax.xticklabelrotation[] = pi/4   # 45 degrees

lines!(ax, x, y)

fig

briochemc · December 8, 2025, 3:27am

In case it was not clear, I believe what @jules meant is that you can do

using CairoMakie
using Dates
fig = Figure()
x = DateTime(2025, 1, 1):Day(1):DateTime(2025, 1, 10) 
ax, plt = lines(fig[1, 1], x, rand(10); axis = (; xticks = x, xticklabelrotation = π/4))

which gives

Note: This has only started working two weeks ago (2025-11-22, with Makie v0.24.7).

lfenzo · December 8, 2025, 12:02pm

Yeah, that is a bit non-intuitive, but it did the trick. I wonder if this behavior should be documented, though. I’m marking this as resolved, thanks @jules, @technocrat, and @briochemc!

Topic		Replies	Views
How to set DateTime format of xlabel using Makie New to Julia makie	3	158	April 2, 2025
Makie: Histogram of DateTime values General Usage question , plotting , makie	3	127	July 17, 2025
Change xticks in Makie.jl recipe Visualization question , makie	2	1058	January 10, 2022
Date axis in Makie New to Julia plotting , makie	11	4321	January 23, 2024
Using dates as axis labels New to Julia glmakie	4	665	December 20, 2021

Makie Axis xticks: passing (datetimes, labels) fails with MethodError

Related topics