Suppose i have points ( 0.9, 79, 76,23, 1, 3, 4.3,89), what is the slope of the line formed by this points
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slope of line formed by arbitary points
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Image Analyst
2013-12-7
Those aren't "points" - it's only the x or only the y values. Please supply actual points.
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Azzi Abdelmalek
2013-12-6
These points don't form one line. Maybe you need to use a curve fitting toolbox to fit a function ax+b
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John D'Errico
2013-12-6
ax+b IS the equation of a straight line. How will the curve fitting toolbox fit a straight line any better than any other fitting tool? Magic?
Azzi Abdelmalek
2013-12-6
Jhon, I have not said it's a better way, just proposed a solution with (maybe). what is yours?
Wayne King
2013-12-6
编辑:Wayne King
2013-12-6
You have not told us what the "x"-values are. If we assume that they are
y = [0.9, 79, 76,23, 1, 3, 4.3,89];
x = 1:length(y); % 1 to 8
You can only fit a least-squares line to this data in order to measure the slope.
X = ones(length(y),2);
X(:,2) = 1:length(y);
y = y(:);
X\y
The intercept is 34.4071 and the slope is 0.0262, but that is a very poor approximation to the data.
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Jos (10584)
2013-12-6
编辑:Jos (10584)
2013-12-6
help polyfit
Note that points are usually defined by coordinates and not by single numbers ...
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Image Analyst
2013-12-7
Try polyfit() to fit (regress) a line through some (x,y) coordinates:
coefficients = polyfit(x, y, 1);
slope = coefficients(1);
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