README.jl

using RDatasets, JDF, DataFrames

a = dataset("datasets", "iris");

first(a, 2)


@time jdffile = JDF.save("iris.jdf", a)
@time a2 = DataFrame(JDF.load("iris.jdf"))


all(names(a2) .== names(a)) # true
all(skipmissing([all(a2[!,name] .== Array(a[!,name])) for name in names(a2)])) #true


a2_selected = DataFrame(JDF.load("iris.jdf", cols = [:Species, :SepalLength, :PetalWidth]))


jdf"path/to/JDF.jdf"


path_to_JDF = "path/to/JDF.jdf"
JDFFile(path_to_JDF)


afile = JDFFile("iris.jdf")

afile[:Species] # load Species column


using Tables
ajdf = JDFFile("iris.jdf")
Tables.columnaccess(ajdf)


Tables.columns(ajdf)


Tables.schema(ajdf)


getproperty(Tables.columns(ajdf), :Species)


jdffile = jdf"iris.jdf"
for col in eachcol(jdffile)
  # do something to col
  # where `col` is the content of one column of iris.jdf
end


jdffile = jdf"iris.jdf"
for (name, col) in zip(names(jdffile), eachcol(jdffile))
  # `name::Symbol` is the name of the column
  #  `col` is the content of one column of iris.jdf
end


using JDF, DataFrames
df = DataFrame(a = 1:3, b = 1:3)
JDF.save(df, "plsdel.jdf")

names(jdf"plsdel.jdf") # [:a, :b]

# clean up
rm("plsdel.jdf", force = true, recursive = true)


@time jdffile = ssavejdf("iris.jdf", a)
@time jdffile = sloadjdf("iris.jdf")


type_compress!(df)


type_compress!(df, compress_float = true)