Linear fit of the points
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James Lorringer
on 9 Sep 2015
Commented: Star Strider
on 9 Sep 2015
Hello, I got a plot (attached). Suppose the plot is simply from:
plot (x,y);
How can I get a linear least squares fit for these three points (they are actually not on one line) and then get the specific x values on the fit when I give certain y values, for example:
2.5:0.025:2.55
Thank you very much!

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Star Strider
on 9 Sep 2015
Edited: Star Strider
on 9 Sep 2015
Probably the easiest way is to use polyfit and polyval. Use an order 1 polynomial to get a straight-line fit.
EDIT— To get the x-values for y-values using polyfit for a straight-line fit, this will work:
b = polyfit(x, y, 1);
x = (y-b(2))/b(1);
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