Timeline for Which CAS can do basic non-commutative differential algebra?
Current License: CC BY-SA 4.0
11 events
| when toggle format | what | by | license | comment | |
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| Jun 20 at 19:01 | vote | accept | M.G. | ||
| Jun 20 at 18:41 | comment | added | Anixx |
@M.G. In any case you can use the Nest function to repeat an operation n times.
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| Jun 20 at 18:38 | comment | added | Anixx | @M.G. I suggest you to ask at Mathematica.SE | |
| Jun 20 at 18:27 | comment | added | M.G. | @Annix: It's neither. It's $(f \partial) (f \partial) (f \partial)$. See my question for the simpler expression $(f\partial)^2$ applied to $f$, i.e. $(f \partial)(f\partial) f = (f\partial)(f f') = f (f' f' + f f'') = f(f')^2 + f^2 f''$. | |
| Jun 20 at 17:52 | comment | added | Anixx | @M.G. I am not sure what this operator is doing and in what sense it is different from $f^3\partial^3$ or $\partial^3 f^3$. | |
| Jun 20 at 17:39 | comment | added | M.G. | This looks great! Could you please also include in your answer a code example for calculating the operator $(\partial f)^3$? I'm not that experienced in Mathematica and I'm still trying to get the hang of it. | |
| Jun 20 at 17:16 | comment | added | Anixx |
@M.G. You can also use dot product: D[(1 + f[t]) . (1 + f[t]), {t, 2}]. As long as the objects are not matrices or lists, it will behave like **.
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| Jun 20 at 16:58 | comment | added | Anixx |
@M.G. You can install the package NCAlgebra mathweb.ucsd.edu/~ncalg and then use NCExpand
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| Jun 20 at 16:53 | comment | added | M.G. | Also, can Mathematica compute explicitly the operator $(f\partial)^3$? This is equally important for me. | |
| Jun 20 at 16:48 | comment | added | M.G. | Yes, this seems to work as desired! Thank you! I was not aware of the non-commutative multiplication option in Mathematica! Quick question, though. Is there a way for Mathematica to better group the terms as in my answer for improved overview of the terms? | |
| Jun 20 at 16:38 | history | answered | Anixx | CC BY-SA 4.0 |