24 lines
536 B
Haskell
24 lines
536 B
Haskell
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module Matrix (Matrix (..), Point, Vector, scale, invert, apply) where
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type Point = (Float, Float)
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type Vector = Point
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data Matrix = Matrix (Float, Float) (Float, Float)
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deriving (Show)
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scale :: Float -> Matrix -> Matrix
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scale r (Matrix (a, b) (c, d)) = Matrix (r * a, r * b) (r * c, r * d)
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invert :: Matrix -> Matrix
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invert (Matrix (a, b) (c, d)) =
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scale
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(1 / (a * d - b * c))
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(Matrix (d, -b) (-c, a))
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apply :: Matrix -> Vector -> Vector
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apply (Matrix (a, b) (c, d)) (x, y) =
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( a * x + b * y,
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c * x + d * y
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)
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