[SOLVED] How to use summarise function in JuliaDB?

How to use summarise function in JuliaDB?

I am following the tutorial published at https://github.com/JuliaComputing/JuliaDB.jl/blob/master/docs/src/tutorial.md
a) While executing:

summarize(mean ∘ skipmissing, flights, :Dest, select = (:Cancelled, :Diverted))

getting:

Error: UndefVarError: mean not defined

b) Also tried:

summarize(mean, dropna(flights), select = :dep_delay)

getting:

Error: UndefVarError: dropna not defined

Please help me in resolving the issue!

Solution

In order to use mean you must first import Statistics or StatsBase. The other problem is due to the fact that dropna should be dropmissing. Also you have a wrong variable name in the second operation.

The lines that work are:

using Statistics
summarize(mean ∘ skipmissing, flights, :Dest, select = (:Cancelled, :Diverted))
summarize(mean, dropmissing(flights), select = :DepDelay)