Today let's look into some pretty neat SymPy functionality. I was in a fluid dynamics lecture, practicing taking notes with LaTeX on the go and stumbled upon this monstrosity:

$$ \Delta(k) = \frac{\rho_1-\rho_2}{\rho_1 + \rho_2} gk + \frac{\gamma k^3}{\rho_1 + \rho_2} - \frac{\rho_1 \rho_2}{(\rho_1 + \rho_2)^2} U^2 k^2 $$

(bonus points for whoever recognizes this!)

We were supposed to draw this for a few example sets of values. All right! I opened up pinta and scribbled a few squiggly lines with my small touchpad, following the blackboard drawings. It looked darn ugly, but that got me thinking. SymPy has parsers, right? Can't I just parse that LaTeX equation into Python and make that plot pretty with matplotlib?

Well, as it turns out, sure...

But it takes some tinkering.

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