I want to convert some symbolic computations from Maple to Julia/SymPy, specifically regarding the Park transformation. Question: how do I use coefficients like sqrt(3/2) and make sure that these are preserved as exact numbers, instead of being converted to a Floting Point number?

You can use Sym to convert coefficients to symbolic expressions in SymPy: julia> using SymPy julia> sqrt(Sym(3//2)) √6 ── 2

Beautiful… I got the same results as in Maple, and with a simpler set-up :-). Questions on subscripts with Julia/SymPy: A final question… I’d like to use subscripts with variable names, if possible. I am able to produce \theta_a by \theta followed by TAB followed by \_a and then TAB. But if I try…

This is more of a Julia question than SymPy, as the unicode subscripts are limited to what they are (on my version of Julia): \_( \_- \_2 \_5 \_8 \_a \_e \_i \_l \_o \_r \_schwa \_v \_) \_0 \_3 \_6 \_9 \_beta \_gamma …

Thanks. Yes, I realize it is a Julia question. For electric machines, the phases are normally referred to as a, b, c, so I would need to use subscripts with a, b and c to make it elegant – as in \theta_a, \theta_b, \theta_c. Anyway, I can live with the less elegant \theta a, \theta b, \theta c.

A final question for now – SymPy and Latexify… In the Latexify tutorial, there is the following example: m = [2//3 "e^(-c*t)" 1+3im; :(x/(x+k_1)) "gamma(n)" :(log10(x))] latexify(m) which leads to: [image] or: julia> show(latexify(m)) L"\begin{equation} \left[ \begin{array}{ccc} \frac{2}{3} & …

Aha. OK, I’ll have to wait for an update of Unicode. I did find that choosing label names like R_a etc. in SymPy expressions actually is shown as R_a in the Out-cell of Jupyter notebooks, so this partially solves my problem. Currently my word processor choice (LyX) doesn’t support Unicode in progra…

Silly SymPy question

New to Julia

nilshg January 7, 2021, 10:51am 6

It actually isn’t a Julia question, but a question of what Unicode supports, see e.g. How is a state of subscript notation in Julia 1.x? - #4 by mbauman

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Silly SymPy question

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