I agree. Hence, the classes I plan to build on top of Prasoon's core will have time-dependent functionality to support motion.
On Thu, Mar 13, 2014 at 11:23 PM, Tim Lahey <[email protected]> wrote: > I think it's necessary to have a reference frame that changes with respect > to time. Even something such as simple link can have a frame that rotates > with respect to the inertial frame. A rotating frame makes dealing with the > equations for a flexible link simpler. Plus, it's useful for multi-body > systems as well. > > Cheers, > > Tim. > > > On 13 Mar 2014, at 13:29, Sachin Joglekar wrote: > > Okay my words may have been a little confusing. To explain the terms >> better- >> *rotated* - oriented at a certain angle wrt the parent system >> *translated* - the origin of the translated system has a non-zero position >> >> vector wrt the parent system >> >> To put it more clearly, the orientation of the child system and the its >> origin's position vector are _not_ functions of time. Essentially, >> Prasoon's code does not deal with time at all. Its good to do simple >> vector >> calculus that does not involve time as a factor. >> By motion, I meant a system whose orientation/translation wrt its parent >> change with time. >> >> >> On Thu, Mar 13, 2014 at 10:50 PM, Jason Moore <[email protected]> >> wrote: >> >> "A coordinate system is a mathematical concept that helps one describe >>> points or vectors(directions) in space. A reference frame, on the other >>> hand, is the extension of this concept to involve motion (time-dependent >>> quantities). Coordinate Systems may be rotated/translated with respect to >>> each other, *but* they are stationary." >>> >>> >>> I don't understand this. How can a coordinate system be rotated and >>> translated yet be stationary. What is your definition of "motion"? >>> >>> >>> Jason >>> moorepants.info >>> +01 530-601-9791 >>> >>> >>> On Thu, Mar 13, 2014 at 12:31 PM, Sachin Joglekar < >>> [email protected] >>> >>>> wrote: >>>> >>> >>> Hello everyone. >>>> >>>> I have put up my proposal for the SymPy/PyDy project on creating a >>>> general-purpose vector calculus module for sympy. It will be a >>>> continuation >>>> of the work that was done by Prasoon and I last summer, and hopefully I >>>> plan to conclude it this time (much of it is currently unmerged). The >>>> details of the project are in my proposal at this link< >>>> https://github.com/pydy/pydy/wiki/GSoC-2014- >>>> Application:-srjoglekar246:-sympy.vector-module> >>>> >>>> . >>>> @Ondrej, Aaron, Stefan - please give your inputs for the same. >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups >>>> "sympy" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an >>>> email to [email protected]. >>>> To post to this group, send email to [email protected]. >>>> Visit this group at http://groups.google.com/group/sympy. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/sympy/28a5bbe3-d6d7- >>>> 40a7-ae9e-6665524bf116%40googlegroups.com<https:// >>>> groups.google.com/d/msgid/sympy/28a5bbe3-d6d7-40a7-ae9e- >>>> 6665524bf116%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> >>>> . >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>>> >>> -- >>> You received this message because you are subscribed to a topic in the >>> Google Groups "sympy" group. >>> To unsubscribe from this topic, visit >>> https://groups.google.com/d/topic/sympy/ux3MVAc9jeQ/unsubscribe. >>> To unsubscribe from this group and all its topics, send an email to >>> [email protected]. >>> To post to this group, send email to [email protected]. >>> Visit this group at http://groups.google.com/group/sympy. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/sympy/CAP7f1Aj2UhWxRyD3bumZ-DnhHNgJ% >>> 3DZ6OJQVhWa9%3Dn3SQVhbDOg%40mail.gmail.com<https:// >>> groups.google.com/d/msgid/sympy/CAP7f1Aj2UhWxRyD3bumZ- >>> DnhHNgJ%3DZ6OJQVhWa9%3Dn3SQVhbDOg%40mail.gmail.com? >>> utm_medium=email&utm_source=footer> >>> >>> . >>> For more options, visit https://groups.google.com/d/optout. >>> >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "sympy" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/sympy. >> To view this discussion on the web visit https://groups.google.com/d/ >> msgid/sympy/CALMMyxZY5ev5-b1gVMGc%3DYroHtw3QHb34W0fFZ3kt7pEdShNY >> g%40mail.gmail.com. >> >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to a topic in the > Google Groups "sympy" group. > To unsubscribe from this topic, visit https://groups.google.com/d/ > topic/sympy/ux3MVAc9jeQ/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/sympy. > To view this discussion on the web visit https://groups.google.com/d/ > msgid/sympy/D52476D7-6B0D-4EFB-98C8-0A1AD20D9F8E%40gmail.com. > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sympy" group. 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