Text and date commands in Spreadsheet
How can I convert a timestamp like "06:55:07.852" to seconds?
I typical have cells in a spreadsheet with such timestamps, and I want to calculate the time difference between two cells (in seconds).
One idea is to split the timestamp string into hours, minutes and seconds using some kind of substring command. But I can not find a GeoGebra command to extract substrings from a cell.