Why can't symbolic variables be logarithmic in Python's sympy?

Why can"t symbolic variables be logarithmic?

an is a symbolic variable, and I want to generate another symbolic variable, ln (a), to display an error. But pow (a pencils 4) is OK. Why?

Matlab python

May.22,2021

sympy does not support Numpy's mathematical calculations (it rewrites itself.), pow is built into python, so it does. Replace it with b=sympy.log (a).

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How to use python symbols to calculate the Jacobi matrix?
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