@acer Thank you I wanted indeed a plain vector.

@tomleslie thank you so much! My mistake was that I did not add parenthesis ("(") before Data and after "BFH". Have a nice evening.

@tomleslie thank you for your help. I really appreciate your commitment to help out people having questions/issues while trying to master maple!

@vv Thank you for your solutions to my questions. However, I still have an issue with my second question. If I want to take the mean of the first column, I get Float(undefined). Could you help me out once more? Thanks in advance.
 

Download Questions.mwQuestions.mw

@acer  Thank you for your solution(s). I am slowly transitioning from a software with less symbolic capabilities, and apparently I need to digest a lot more before I will be able to use Maple efficiently. 

@tomleslie thank you for your informative answer. As a newbie to Maple I still have a lot to learn.

Thank you both for your answers!

@acer

Thank you all for your additional comments and remarks as they help me in slowly ameliorating my Maple knowledge. 

Dear Acer, Thank you for your answer. I admit this is a much nicer and clearer way of doing elementwise calculus.

@tomleslie Thank you, appreciate your time

@tomleslie  Your solution works but what puzzles me is why I need to use the convert command and why I cannot just right click the result for 'test' and choose a different unit. Thank in advance for your help!

@tomleslie  Thank you!

@dharr that was the solution, thanks a lot!

@tomleslie Thank you so much for your educative help. Enjoy Holloween

@dharr  Thank you for your reply. I was able to use Bloodpath now as upper limit in my plot and in the ODE; I could solve my conversion issue by: P__b := convert(convert(P__baroCor, 'units', 'mmHg'), unit_free)

However your solution sol(Bloodpath) for getting the value at Bloodpath does not seem to work Could you help me out once more?

Thanks in advance