ln() vs. log()

[emece67]

(04-20-2016 07:33 AM)Csaba Tizedes Wrote:  BTW: Has anybody a technical application where you can (must to) use both LOG() and LN() or these inverses (in any permutation)?

Csaba

When working on acoustics the dB is always present, so you use \(\log/10^x \).

If, working on acoustics, you deal with horns, many times such horns are exponential ones and you also use \(\ln/e^x \). I suppose that this also applies to people working with microwave horns.

There are other uses of \(\ln/e^x \) in EE, such as the Ebers-Moll equations (of bipolar transistors), diode equation, skin effect,... So if you work with any of them and also use dB, you need both kind of logs. Also, the magnetic Reynolds number many times goes into an exponential function \(e^{-R_m}\).

In information theory \(log_2 \) is of interest. In fact I many times use both of \(\log/\log_2 \). Unfortunately, I only got a calculator with direct \(\log_2\) quite lately (wp34S).

But if you are asking for a single equation using both of \(\log/\ln \), none comes to my mind.

Regards.

p.s. Why on Earth is so difficult to me to enter the combinations "\ (" and "\ )" needed to write equations here? Perhaps an artefact of the Spanish keyboard layout.