Logarithmic Scaling

[mrberman87]

I don't see anything for doing logarithmic scaling of certain units. Are there any plans to support logarithmic scales?

This would be very useful for, at least, RF electronics that I know of, and probably many other use cases. For example, RF Power is often measured in terms of dBm, which is a 10*log(power / milliWatts) scaling; 1 Watt = 30 dBm, 100 Watts = 50 dBm, etc. In electronics, voltage and current gain are also represented on a logarithmic scale.

[mpusz]

This is still an open question. Please see #35 for more info on this subject.

I think that the current state is that we agreed that the logarithmic (and any other scale) can be covered by a dedicated user-specific representation type (Rep) passed to the quantity class template.

[mrberman87]

Okay. I didn't see anything talking about this, and I wasn't sure.

Thank you for clarifying.

[mpusz]

What is your opinion on this? Does a custom representation type cover your requirements and use cases?

[mrberman87]

As long as it can easily be hooked in, I don't see an issue with that. As far as my use case, electronics, scales are going to be 10log10(Power/Power) or 20log10(Voltage/Voltage) or 20*log10(Current/Current), and these all are represented in decibels (dB). The interesting thing with these particular ones though is that there are technically no units, as they are used for ratios, but of course there is a standard for Power with dBm where a given RF power level is compared to 1 milliWatt. There are a few other common ones in Wikipedia (https://en.wikipedia.org/wiki/Logarithmic_scale) though.

[mrberman87]

I see now that there has already been a discussion on this that I missed. #35