[Scipy-svn] r2597 - trunk/Lib/odr

scipy-svn at scipy.org scipy-svn at scipy.org
Tue Jan 23 14:15:52 CST 2007


Author: jarrod.millman
Date: 2007-01-23 14:15:49 -0600 (Tue, 23 Jan 2007)
New Revision: 2597

Added:
   trunk/Lib/odr/info.py
Log:
whoops.  here is the info.py


Added: trunk/Lib/odr/info.py
===================================================================
--- trunk/Lib/odr/info.py	2007-01-23 20:14:51 UTC (rev 2596)
+++ trunk/Lib/odr/info.py	2007-01-23 20:15:49 UTC (rev 2597)
@@ -0,0 +1,44 @@
+"""Orthogonal Distance Regression
+
+Introduction
+============
+
+Why Orthogonal Distance Regression (ODR)? Sometimes one has measurement errors
+in the explanatory variable, not just the response variable. Ordinary Least
+Squares (OLS) fitting procedures treat the data for explanatory variables as
+fixed. Furthermore, OLS procedures require that the response variable be an
+explicit function of the explanatory variables; sometimes making the equation
+explicit is unwieldy and introduces errors. ODR can handle both of these cases
+with ease and can even reduce to the OLS case if necessary.
+
+ODRPACK is a FORTRAN-77 library for performing ODR with possibly non-linear
+fitting functions. It uses a modified trust-region Levenberg-Marquardt-type
+algorithm to estimate the function parameters. The fitting functions are
+provided by Python functions operating on NumPy arrays. The required derivatives
+may be provided by Python functions as well or may be numerically estimated.
+ODRPACK can do explicit or implicit ODR fits or can do OLS. Input and output
+variables may be multi-dimensional. Weights can be provided to account for
+different variances of the observations (even covariances between dimensions of
+the variables).
+
+odr provides two interfaces: a single function and a set of high-level classes
+that wrap that function. Please refer to their docstrings for more information.
+While the docstring of the function, odr, does not have a full explanation of
+its arguments, the classes do, and the arguments with the same name usually have
+the same requirements. Furthermore, it is highly suggested that one at least
+skim the ODRPACK User's Guide.  Know Thy Algorithm.
+
+
+Use
+===
+
+See the docstrings of odr.odrpack and the functions and classes for
+usage instructions. The ODRPACK User's Guide is also quite helpful. It can be
+found on one of the ODRPACK's original author's website:
+
+    http://www.boulder.nist.gov/mcsd/Staff/JRogers/odrpack.html
+
+Robert Kern
+robert.kern at gmail.com
+"""
+postpone_import = 1



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