Least-squares line fitting: Difference between revisions
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A WASSERMANN (talk | contribs) No edit summary |
A WASSERMANN (talk | contribs) No edit summary |
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} | } | ||
brd.unsuspendUpdate(); | brd.unsuspendUpdate(); | ||
// Having constructed the points, we can fit a circle | // Having constructed the points, we can fit a circle | ||
// through the point set, consisting of n points. | // through the point set, consisting of n points. | ||
// The (n times 3) matrix consists of | // The (n times 3) matrix consists of | ||
// x_1, y_1 | // 1, x_1, y_1 | ||
// x_2, y_2 | // 1, x_2, y_2 | ||
// ... | // ... | ||
// x_n, y_n | // 1, x_n, y_n | ||
// where x_i, y_i is the position of point p_i | // where x_i, y_i is the position of point p_i | ||
// | // y is equal to the zero vector. | ||
var M = [], y= [0.0,0.0,0.0], MT, B, c, z, n; | |||
var M = [], y = [], MT, B, c, z, n; | |||
n = p.length; | n = p.length; | ||
for (i=0;i<n;i++) { | for (i=0;i<n;i++) { | ||
M.push([ | M.push([1.0, p[i].X(), p[i].Y()]); | ||
} | } | ||
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// Finally, we can read from the solution vector z the coordinates [xm, ym] of the center | // Finally, we can read from the solution vector z the coordinates [xm, ym] of the center | ||
// and the radius r and draw the circle. | // and the radius r and draw the circle. | ||
var xm = z[0]*0.5; | //var xm = z[0]*0.5; | ||
var ym = z[1]*0.5; | //var ym = z[1]*0.5; | ||
var r = Math.sqrt(z[2]+xm*xm+ym*ym); | //var r = Math.sqrt(z[2]+xm*xm+ym*ym); | ||
brd.create('line',z); | |||
</jsxgraph> | </jsxgraph> | ||
