Spread
Spread gives one measure to the 'separation' of two lines (replacing 'angle'): a dimensionless number in the range '0' (parallel) to '1' (perpendicular), which can have several interpretations.
- Trigonometric: as the sine-ratio for the quadrances in a right triangle (and therefore equivalent to the square of the sine of the angle).
- Vector: as a rational function of the slopes (or directions) of two lines where they meet.
- Cartesian: as a rational function of the three co-ordinates used to describe these two vectors.
- Linear algebra: as a normalized rational function of the square of the determinant of two vectors (from three points) divided by the product of their quadrances.
Read more about this topic: Rational Trigonometry
Famous quotes containing the word spread:
“Strike on your drummes, spread out your ancyents!
Sound out your trumpetts, sound out amaine!”
—Unknown. Sir Andrew Barton. . .
English and Scottish Ballads (The Poetry Bookshelf)
“A feme may come, leaf-green,
Whose coming may give revel
Beyond revelries of sleep,
Yes, and the blackbird spread its tail,
So that the sun may speckle,
While it creaks hail.”
—Wallace Stevens (1879–1955)
“none
Thought of the others they would never meet
Or how their lives would all contain this hour.
I thought of London spread out in the sun,
Its postal districts packed like squares of wheat:”
—Philip Larkin (1922–1985)