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!FitLine
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Text File
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1994-04-16
|
3KB
|
64 lines
+=========================================================================+
| |
| FitLine |
| |
+=========================================================================+
| |
| by Mike Williams |
| |
| 111 Evering Road, London N16 7SL |
| |
+=========================================================================+
| |
| This program is in the public domain and may be copied |
| freely as long as no profit is made in the process |
| |
+=========================================================================+
Overview
========
This program fits the best straight line to a number of points.
If you perform an experiment and you think that there may be a linear
relationship between the input and output parameters, then this program will
find that relationship.
Drop a text file containing a list of X and Y coordinates onto the iconbar
icon.
Input File
==========
The input should be in a text file, and should be a list of pairs of numbers
separated by spaces, commas or newline characters. The following are all
valid and indicate the same point.
1 -2.5
1,-2.5
1
-2.5
Any characters other than 0123456789-. are assumed to be comments and are
ignored. *WARNING* do not use the characters "-" or "." in any comments as
these will be construed as numerics.
There must be at least two points (i.e. four values) in the input file.
Best Fit
========
The best fit line is defined to be the line which minimizes the sum of the
squares of the error distances. (Least Squares Method).
The program does not comment on how good a fit this is. Given a cloud of
completely random points, the program will still produce a best fit line. A
graph is drawn, showing the points and the line. It is up to you to decide
if a straight line is a sensible representation of the data.
If you think that the best fit may be a power function of the form
"y = K*x^n" then you can drop the same input file onto !FitPower, and see if
that looks any better.