Possibilly, a bug in the log10(x) function

[pu5frs]

Dear Qucstudio developer,

 

Thank you very much for keeping this software available and up to date.

I believe there is a problem with the log10(x) function for values  of x in the range [0,1]. The output is positive rather than negative as expected. The function dB(x) does well.  Below is an image for a better understanding.

Thanks

PU5FRS

 

 

 

[QucsStudio]

Because s-parameters are complex-valued, log10(…) gives a complex number, too.  In rectangular diagrams, the magnitude is shown, which is always positive.

20*log10(abs(S[3,3])) is what you want.

[pu5frs]

Thanks.

[Author]

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