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I'm doing plate reduction on astro photos. There's non-linearity in the
lens. Basically, one is trying to estimate several lens parameters by
look at a field of known stars versus ones measured on a photo plate.
The author states it can be solved by taking first derivatives to
linearize matters, and iteratively apply least squares until the change
in parameters falls below some limits. Gauss-Newton seems a bit
different in that it tries to minimize the sum of squares. <br>
<br>
In a follow up paper, he refers to the process as a gradient method.
Up until then, my best guess was G-N. I suspect that you are hinting at
the Gradient plus LSQ (least squares). However, out of curiosity,
isn't their a library of optimization methods like Marquardt or
Davidon? <br>
<br>
On 5/28/2010 12:09 PM, Charles R Harris wrote:
<blockquote
cite="mid:AANLkTikH5h2ak5wpLhB6E5JGlHUgUCMe-5ZllzyOk1y0@mail.gmail.com"
type="cite">What problem are you trying to solve. The leastsq
algorithm in scipy is effectively Gauss-Newton when that is appropriate
to the problem. <br>
<br>
Chuck<br>
<br>
<div class="gmail_quote">On Fri, May 28, 2010 at 12:36 PM, Wayne
Watson <span dir="ltr"><<a moz-do-not-send="true"
href="mailto:sierra_mtnview@sbcglobal.net">sierra_mtnview@sbcglobal.net</a>></span>
wrote:<br>
<blockquote class="gmail_quote"
style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Is
Subject method available in Python?<br>
<br>
--<br>
Wayne Watson (Watson Adventures, Prop., Nevada City, CA)<br>
<br>
(121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)<br>
Obz Site: 39° 15' 7" N, 121° 2' 32" W, 2700 feet<br>
<br>
There are no statues or memorials dedicated to<br>
Thomas Paine for his substantial part in the<br>
American Revolution.<br>
<br>
-- An observation in The Science of Liberty<br>
by Timoth Ferris<br>
<br>
<br>
Web Page:<<a moz-do-not-send="true"
href="http://www.speckledwithstars.net/" target="_blank">www.speckledwithstars.net/</a>><br>
<br>
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<pre class="moz-signature" cols="72">--
Wayne Watson (Watson Adventures, Prop., Nevada City, CA)
(121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
Obz Site: 39° 15' 7" N, 121° 2' 32" W, 2700 feet
There are no statues or memorials dedicated to
Thomas Paine for his substantial part in the
American Revolution.
-- An observation in The Science of Liberty
by Timoth Ferris
Web Page: <<a class="moz-txt-link-abbreviated" href="http://www.speckledwithstars.net/">www.speckledwithstars.net/</a>></pre>
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