Cytomic SVF analysis thread

[soundmodel]

I am creating a general thread for the analysis of the Cytomic SVF paper.

https://cytomic.com/files/dsp/SvfLinear ... mised2.pdf

Because I am finding it a bit hard to read.

My first question is about disappearing c^{n+1} term in e.g. http://www.cytomic.com/files/dsp/OnePol ... owPass.pdf. However, it seems to disappear in other models too.

So if we use eq (1) ic^{n+1} = gc vc^{n+1} - iceq^n and eq (4) ir = gr vr, then

why does

0 = gr (v0 - v1) - (gc (v1 - 0) - ic1eq)

have the term gcv1 rather than gcv1c^2 as I also interpreted that n=1 based on ic1eq.

[Archit3ch]

There is no c term. vc is the voltage across the capacitor and ic is the current through the capacitor. n is the current time step.

[andy-cytomic]

The iceq term stores all previous energy contributions. The gc capacitor conductance term is derived from the capacitor value C.

[soundmodel]

There is no c term. vc is the voltage across the capacitor and ic is the current through the capacitor. n is the current time step.

Oh, so you mean they're actually like g_c and v_c?

[andy-cytomic]

The n and n+1 terms are designators for which sample in the time series we are talking about, they are not powers. Think of n+1 as being the new sample being solved for, n being a current sample and n-i being previous samples, which contributions normally get bundled up into the single iceq term.

[soundmodel]

The n and n+1 terms are designators for which sample in the time series we are talking about, they are not powers. Think of n+1 as being the new sample being solved for, n being a current sample and n-i being previous samples, which contributions normally get bundled up into the single iceq term.

Anyways, I think the notation could be better.

Or you could've declared the used notation at the beginning. E.g. that "^n+1 := [n+1]".

[gaggle of hermits]

n and n+1 are hardly unusual designators in dsp.

[andy-cytomic]

This is circuit simulation, so I've based the notation from the QUCs technical pages: https://qucs.sourceforge.net/tech/node24.html

[mystran]

This is circuit simulation, so I've based the notation from the QUCs technical pages: https://qucs.sourceforge.net/tech/node24.html

For what it's worth.. your notation (or perhaps more so the formatting of the same) does make it a bit difficult to parse visually. In TeX I'd probably go for subscript for the components (eg. {i_c}^n and {v_c}^n or something) to help with the grouping, but .. no idea if that'd be any cleaner in non-TeX.

Not a big deal.. but makes it look scarier than it actually is.

[Urs]

I think that's because it's not any form of text formatting. It's simply the math input from the CAS.

I'm intrigued at how efficient Mathematica input is as opposed to Maple (which I use), but I too find it very difficult to parse.

[andy-cytomic]

Mathematica lets you use arrows to move around expressions visually and has decent shortcuts to stick something at a diagonal to the current expression. I've not used maple much.