Vector changes
Tests for new gem
Writing vector accessors
Basic vector should be complete
Writing dataframe
Dataframe array constructor in progress
Dataframe init wip
Starting with []
Dataframe and vector basic inits done
DataFrame validation and []= tests.
Finished []= for single vector assignment
Tests for each iterators
Tests for accessors
Easy accessor classes
Easy accessorts
More tests and better row and vector accessors
Assignment for vector and tests for new row creation.
Part of DF#insert_row and tests for DV#concat
DF#row setter and Index#to_index bug fix
DF#each-type iterators for rows and vectors