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addressing the rendering versus verifiability challenge

Published 2016-05-26T02:54:00Z by Physics Derivation Graph

For the Physics Derivation Graph, the primary output is visual. Thus rendering expressions should be beautiful. Latex is a natural choice and the entry is intuitive and straightforward.

In addition to rendering, the other task is to verify that the content is correct. This means using a computer algebra system (ie Mathematica, Octave). Latex is not amenable to CAS input because Latex can be mathematically ambiguous -- resolution depends on context.

One way to resolve this would be to stick with Latex, then convert to a CAS format for verifying correctness.


As an example, suppose I want to check that the expression "multbothsidesby" was correctly entered for input T/f=1, output T=f, with feed f. The Sage syntax looks like

input_expr = T/f==1
expected_output_expr= T==f
expected_output_expr == input_expr*f

The above Sage returns true, building confidence that the step is valid. More simply,

(T==f) == ((T/f==1)*f)

If Latex is to be used as the input, then we need to convert it to Sage syntax.
In addition to using a Sage notebook (, there's a one-time eval option --
Calling a local installation of Sage is possible from Python, see