Unstack column is very slow for large data

Version: 2019b

Type: Bug Fixes

Category: Data Handling

Subcategory: Worksheet Data Manipulation

Jira: ORG-19654

E.g. for a data with 3 million rows, unstack column in 2019 took about 300 sec while in Origin 2019b, it only takes about 20 sec.

Note: If group column is set as categorical, the unstacking speed can be a little faster.