Hi! I'm playing with electronic circuits simulation (with LTSpice IV) and can get interesting curves like this one.

I of course also get a csv file containing the numbers that are used to display this curve.
Is there a simple way to deduce biquad filter parameters from that?

This kind of curve look A LOT like a resonant low-pass (for which you can easily find biquad parameters).

Indeed it looks like one, the thing I'm missing is the method to get those parameters
How can I translate the peak frequency, gain @ peak frequency and slope into those parameters?

@barbouze I think you will have to experiment to find the values......
The frequency should be the cut-off frequency, which, looking at your graph could be about 10kHz.
The gain is the relative level that you want to get to........ here it is maybe -6.3dB. But 50 as an input for [biquad~] is zero (flat) (in "equaliser" mode) so I would try about 43.4 and you might be lucky.
The slope is the dB per octave, but in [biquad~] it has a grain of 100 (100=1 octave)....... so it looks as though the slope is about 100........ it should get to -6.3dB in one octave (10kHz doubled = 20kHz).
So I would say to use the high-shelf settings........ but high-shelf and low-shelf only have positive gain if I remember correctly (I am almost certain that I must be wrong about that!!!!!!!).
So (if I am correct) you will have to use low-shelf and then correct for the added gain automatically in your patch.
This might help.......4band.pd
David.

Thanks for the help! I'll try that way, it's seems quite easy.
One last question, let's say that the signal goes trough multiple filters (one low pass and then 2 high pass with different settings). Is it possible to generate a curve by sweeping a sine from 20Hz to 20kHz and apply that curve as a filter in the same way you can use impulse response for reverbs?

@barbouze Yes, you could plot amplitude against time for the duration of the sweep using [tabwrite~]....
Or you could use this free software.......... http://www.roomeqwizard.com/
David.

I mean I can already plot the curve, I was just asking if there was a way to apply the frequency response described by that curve to the signal.

Take a look at example 3.8.2.1 on Johannes Kreidler's site:

http://pd-tutorial.com/english/ch03s08.html

Is that what you're after?

Yes! Thanks a lot!