Questions and discussion for this lecture live here. Fire away by hitting Reply below 
I was having trouble with the animation (in this lecture and all following lectures which included animation) and getting an error: “Javascript Error: IPython Is Not Defined”. I made the following change and it started working (but I will say I’m new to Python so I’m not sure if this is a good fix).
%matplotlib notebook
Changed to:
%matplotlib widget
Also, I often had to restart the entire kernal if making any changes to any plot, otherwise the same error would occur when using matplotlib.
Thanks for posting this update Dan, much appreciated.
S
Hello Sean,
I’m curious about why we don’t include phase angle terms in the response of masses. By not having separate phase angle variables for each mass, it seems we are limited to only 0 or 180 degrees of phase shift between the responses. Does this assumption always hold true?
I’d appreciate any insights you can provide.
Thanks!
Hey @Shakib.Ayoubzadeh - remember that the modal responses are at different frequencies - as such, phase angle is not a meaningful parameter in this context as phase is only something we measure between oscillations of the same frequency.
S