Author Topic: Linear Fit question  (Read 911 times)

Offline aworonow

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Linear Fit question
« on: 2016 November 28 09:46:09 »
If I set a linear image as the reference image, and apply LinearFit to another linear image, is the resulting image also linear? I would presume so, as long as "linear fit" means first-order linear. But not sure.

Is there a PI tool I could have used to answer my own question?

Thanks, Alex

Offline RickS

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Re: Linear Fit question
« Reply #1 on: 2016 November 28 16:02:40 »
If I set a linear image as the reference image, and apply LinearFit to another linear image, is the resulting image also linear?

Yes, the result will be linear.  LinearFit applies a linear fitting function of the form y = a + b*x (see http://pixinsight.com/forum/index.php?topic=2302.msg15289).

Is there a PI tool I could have used to answer my own question?

A poke around with the readout mode cursor, perhaps?

Cheers,
Rick.


Offline aworonow

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Re: Linear Fit question
« Reply #2 on: 2016 November 28 16:25:53 »
Thanks, Rick.