comp.lang.idl-pvwave archive - RDF feed
type: channel
description: Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
items: Optimisation in IDL?
items: Re: Optimisation in IDL?

Optimisation in IDL?
type: item
description: I have following optimisation problem and want to ask if anybody could give me some hints for implementing it in IDL. There is a function, depending on given x,y and g values (simply the x,y values of 2D image pixels and their grey levels g). I have to find the maximum of the following function and the constants a and b should be calculated: MAX(Sum1 (Sum2 (Dirac(log(g(x,y) - ax -by -g))))), where Sum1 is the sum over all possible grey values, Sum2 is the sum over all possible x,y values and Dirac is the dirac function. The function itself is not the problem, rather the algorithm for finding the right constants a and b. Thanks for any input, Helmut Ahammer
creator: helaha
date: 2004-10-18T14:13:51-00:00

Re: Optimisation in IDL?
type: item
description: Hi, I would use Craig Markwardt�s MPFIT routine: http://cow.physics.wisc.edu/~craigm/idl/fitting.html -- luxx. "Ahammer Helmut" <helaha@gmx.net> schrieb im Newsbeitrag news:f2c7de6c.0410180613.557e31a9@posting.google.com... > I have following optimisation problem and want to ask if anybody could > give me some hints for implementing it in IDL. > There is a function, depending on given x,y and g values (simply the > x,y values of 2D image pixels and their grey levels g). > I have to find the maximum of the following function and the constants > a and b should be calculated: > MAX(Sum1 (Sum2 (Dirac(log(g(x,y) - ax -by -g))))), > where Sum1 is the sum over all possible grey values, Sum2 is the sum > over all possible x,y values and Dirac is the dirac function. The > function itself is not the problem, rather the algorithm for finding > the right constants a and b. > > Thanks for any input, > Helmut Ahammer
creator: luxx
date: 2004-10-23T22:34:12-00:00