An interior-point gradient method for large-scale totally nonnegative least squares problems

Igor code for solving NNLS problems, coded using: http://www.caam.rice.edu/~zhang/reports/tr0408.ps (Michael Merritt and Yin Zhang, Technical Report TR04-08, Department of Computational and Applied Mathematics, Rice University, Houston, Texas 77005, U.S.A., May, 2004)
Abstract: We study an interior-point gradient method for solving a class of so-called totally nonnegative least squares problems. At each iteration, the method decreases the residual norm along a diagonally scaled negative gradient direction with a special scaling. We establish the global convergence of the method, and present some numerical examples to compare the proposed method with a few similar methods including the affine scaling method.
This code is extracted from "Irena" package for modeling of small-angle scattering,where it is used for solving size distribution problem in small-angle scattering. Similar method is Maximum Entropy, regularization, etc.
Note: as coded can handle ONLY 1D data. The input data are in form of MeasuredData (as three waves: one with X values, one with Y values, and one with Uncertainties), and Model which is being desired (as two waves: one with X values and one with Y values). The code returns Y values for the Model. Please, read the reference for more details.

Project Details

Current Project Release

An interior-point gradient method for large-scale totally nonnegative least squares problems IGOR.6.00.x-1.1

Release File: IPGM_TNNLS_0.ipf (6.25 KB)
Version: IGOR.6.00.x-1.1
Version Date:
Version Major: 1
Version Patch Level: 1
OS Compatibility: Mac-Intel Windows
Release Notes: Debugged and tested version. Found two bugs in original release resulting in incorrect result. Tested against original code in Irena package.
View All Releases

Forum

Support

Gallery

Igor Pro 10

Learn More

Igor XOP Toolkit

Learn More

Igor NIDAQ Tools MX

Learn More