## asymmetrical distribution functions

Lautibah
Posts: 54
Joined: January 5th, 2019, 12:41 pm

### asymmetrical distribution functions

Hello.

I want to ask: is there any asymmetrical distribution function implemented on MagicPlot? I have seen that the skew function is a really good function but it depend on the "error function" that magicplot does not support. I have seen that MagicPlot contains the "skewness" index but nothing related with fitting a curve with a function.

Is there any similar things in Magic Plot? I can, obviously, fit an asymmetric function as a sum of symmetrical functions but it doesn't have physical sense.

Thanks

MagicPlot
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### Re: asymmetrical distribution functions

Hello Lautibah,

Unfortunately, asymmetrical distribution functions are not implemented. What exactly predefined formulas do you need? BTW, we plan to add special functions (including errf()) in near future.

Lautibah
Posts: 54
Joined: January 5th, 2019, 12:41 pm

### Re: asymmetrical distribution functions

I think we need the skew function, because I have no much clues about how to fit the graph attached. As you'll see, at low Hz values it looks like a gaussian curve (it fits good there), but while the frequency increases the curve gets wider and asymmetrical. We believe that what we are seeing two asymmetrical functions start together and are really similar each from the other and, as the frequency increases, they behave differently giving as a result e.g. the red one.
We need to deconvolution the curve in two

Thanks

Edit: well... I have found the Log-normal curve and it kind of do the job, but I am still curious about the skew funct
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