Products > Test Equipment

Pocket-Sized 6 GHz 1 TS/s ET Scope

<< < (38/107) > >>

SJL-Instruments:
The weights shouldn't multiply anything. They should be used to perform a weighted least squares fit to the line.
(i.e. pass g'(F)^-2 into the weight input of the LabView Linear Fit VI.)

A closed-form formula for g' is g'(x) = sqrt(pi) * exp(g(x)^2).
To get the appropriate weights, evaluate g'(F)^-2 at each CDF value F.

joeqsmith:
Opps,  got the weights.   I'm still stuck on the g'(0) = 1.772.  Guessing you are not suggesting the derivative of 0. 

Remember when using a scope meant adjusting a few knobs?   :-DD

SJL-Instruments:
You can use the formula g'(x) = sqrt(pi) * exp(g(x)^2).
In other words, g'(x)^-2 = exp(-2 g(x)^2)/pi. Put that directly into the least-squares weight.
You've already computed g(x) at every point, so this should be a small change.


--- Quote from: joeqsmith on January 30, 2024, 01:05:37 am ---Remember when using a scope meant adjusting a few knobs?   :-DD

--- End quote ---
LabView interface is now on our todo list.  ;D

joeqsmith:
If correct ...

SJL-Instruments:

--- Quote from: joeqsmith on January 30, 2024, 01:36:41 am ---If correct ...

--- End quote ---
Weights should read 0.3183, 0.1568, 0.1568. (i.e. exp(-2x^2)/pi applied to InvGauErr.)
Not sure what leastsq means. It's not really meaningful unless you run it on actual data.

Navigation

[0] Message Index

[#] Next page

[*] Previous page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod