Complicated expressions with logarithm return incorrect results

[JakubVanek]

Hi! I've noticed that mate-calc sometimes gives wrong results of some computations.

Expected behaviour

-ln(20/100)/sqrt(pi^2+ln(20/100)^2) evaluates to 0.4559498107691261 (calculated by Python)

Actual behaviour

It evaluates to -0.624079067+1.218190647i.

Steps to reproduce the behaviour

Just enter the expression above to mate-calc.

MATE general version

1.24.0 from Ubuntu 20.04

Package version

Current HEAD of this repository (commit 665bbc0).

Linux Distribution

Ubuntu 20.04.

Link to bugreport of your Distribution (requirement)

I don't see how this applies here given that the issue reproduces on a clean build of mate-calc (albeit relying on distro's packaging of MATE core).

[JakubVanek]

Oh, it seems that the top logarithm is applied on the whole (20/100)/sqrt(pi^2+ln(20/100)^2) and not just on (20/100).

[JakubVanek]

Oh well, even the issue described in #168 still happens - -ln(1) is calculated as pi*i.