DataContainer.query() missing unit conversion?

Should DataContainer.query() include unit conversion? Or where will this happen? Ideally, I would like DataContainer to hold the data in its original form and then convert, slice, etc. upon query. Subsequent queries would start from the original data. Ideally, the enduser will be able to also inspect this DataContainer to verify its correctness. Today, that's impossible for some plotting functions and hard to do for others.

Start by locating DataContainer.query() and the plotting functions that currently make unit conversion difficult to inspect. Clarify whether original data must remain available while queried results are converted or sliced, and define the expected behavior for subsequent queries and end-user inspection before implementation.

Written by the indexing model from the issue text.