Interpolations between timeseries (#8)

Project.toml

@@ -7,6 +7,7 @@ version = "1.0.0-DEV"
 CSV = "336ed68f-0bac-5ca0-87d4-7b16caf5d00b"
 DataFrames = "a93c6f00-e57d-5684-b7b6-d8193f3e46c0"
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"
+Interpolations = "a98d9a8b-a2ab-59e6-89dd-64a1c18fca59"
 Measurements = "eff96d63-e80a-5855-80a2-b1b0885c5ab7"
 Plots = "91a5bcdd-55d7-5caf-9e0b-520d859cae80"
 Revise = "295af30f-e4ad-537b-8983-00126c2a3abe"

src/Experiments.jl

@@ -6,6 +6,7 @@ using TimeSeries
 using Dates
 using DataFrames
 using CSV
+using Interpolations
 
 include("types.jl")
 include("datetime_handling.jl")

src/datetime_handling.jl

@@ -90,4 +90,8 @@ julia> duration(experiment)
 """
 function duration(experiment::Experiment)
     return Dates.canonicalize(endtime(experiment) - starttime(experiment))
+end
+
+function timestamp2hours(timeseries::TimeArray)
+    return (timestamp(timeseries) .- starttime(timeseries)) ./ Dates.Hour(1)
 end

src/importers.jl

@@ -46,4 +46,9 @@ function timeseries(experiment::Experiments.Experiment, names::Symbol...)
         return ts_vec[1]
     end
     return merge(ts_vec..., method = :outer)
+end
+
+function interpolate(from_ts::TimeArray, to_ts::TimeArray)
+    lin = linear_interpolation(Experiments.timestamp2hours(from_ts), vec(values(from_ts)), extrapolation_bc=Line())
+    return timeseries(Symbol(meta(from_ts), :_interp), timestamp(to_ts), lin.(Experiments.timestamp2hours(to_ts)))
 end

test/usecases.jl

@@ -5,6 +5,7 @@ using Plots
 using Dates
 using CSV 
 using DataFrames
+using Interpolations
 
 # First, creating some measurements from fermentations
 df_offline = CSV.read("data/offline.csv", DataFrame)
@@ -52,4 +53,12 @@ Experiments.calc!(experiments, Experiments.diff, :OD, :DCW, :p_O2)
 experiments
 
 # interpolation
-ts = Experiments.timeseries(exp, :OD)
+ts = Experiments.timeseries(exp, :OD)
+lin = linear_interpolation(Experiments.timestamp2hours(ts), vec(values(ts)), extrapolation_bc=Line())
+plot([0:0.1:37], lin.([0:0.1:37]), label="interpolated")
+scatter!(Experiments.timestamp2hours(ts), vec(values(ts)), label="original")
+OD_2 = Experiments.interpolate(ts, pO2)
+meta(OD_2)
+plot(values(pO2),values(OD_2))
+plot!(pO2)
+