DataFrame can not be initialized with missing values

[olekscode]

It would be useful to initialize a DataFrame with the following "incomplete" array and have it automatically insert nil or Float nan in place of the missing values. It should also be possible to handle these values later.

DataFrame fromRows: #(
    (1 2 3)
    (4 5)).

[SergeStinckwich]

A better support for missing values like the one you can find in R or Python is needed.

https://www.statmethods.net/input/missingdata.html