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I like the convenient unit syntax, if this works well with IntervalArithmetic.jl, julia can become a competitor to Frink https://frinklang.org/ https://frinklan

• eigenspace 7y ago
  Here's an example of them working together rather effortlessly: using Unitful, IntervalArithmetic const m = u"m" const k = 2π/10m f(x) = cos(k * x)/(k^2 - 1/x^2) julia> f((10.0 ± 0.1)m) [2.5924, 2.60024] m^2 If I try to put in a dimensionally incorrect argument to f, I get an error: julia> f((10 ± 0.01)u"s") ERROR: MethodError: no method matching cos(::Quantity{Interval{Float64},𝐓*𝐋^-1,Unitful.FreeUnits{(m^-1, s),𝐓*𝐋^-1,nothing}}) Closest candidates are: cos(::Float16) at math.jl:1085 cos(::Complex{Float16}) at math.jl:1086 cos(::Missing) at math.jl:1138 ... This isn't the most friendly error message in the world, but that can certainly be worked on and with a bit of patience it's pretty clear that it's saying that the problem was that it tried to compute the cosine of a unitful quantity which is nonsense. _____________________________________ Unfortunately I had to use unitful intervals (i.e. (10.0 ± 0.1)m) instead of intervals of uniful quantities (i.e. 10.0m ± 0.1m) because IntervalArithmetic.jl demands that it takes real quantities, but Unitful quantities are subtypes of Number instead of Real.
  • eigenspace 7y ago
    Just as a followup, I just realized that the Measurements.jl package does know how to deal with non-real uncertainties, so one can instead do using Unitful, Measurements const m = u"m" const k = 2π/10m f(x) = cos(k * x)/(k^2 - 1/x^2) julia> f(10.0m ± 0.1m) (2.5989 ± 0.0014) - (0.0 ± 0.16)im m^2