2 module Complex(Complex((:+)), realPart, imagPart, conjugate, mkPolar,
3 cis, polar, magnitude, phase) where
7 data (RealFloat a) => Complex a = !a :+ !a deriving (Eq,Read,Show)
9 realPart, imagPart :: (RealFloat a) => Complex a -> a
13 conjugate :: (RealFloat a) => Complex a -> Complex a
14 conjugate (x:+y) = x :+ (-y)
16 mkPolar :: (RealFloat a) => a -> a -> Complex a
17 mkPolar r theta = r * cos theta :+ r * sin theta
19 cis :: (RealFloat a) => a -> Complex a
20 cis theta = cos theta :+ sin theta
22 polar :: (RealFloat a) => Complex a -> (a,a)
23 polar z = (magnitude z, phase z)
25 magnitude, phase :: (RealFloat a) => Complex a -> a
26 magnitude (x:+y) = scaleFloat k
27 (sqrt ((scaleFloat mk x)^2 + (scaleFloat mk y)^2))
28 where k = max (exponent x) (exponent y)
31 phase (x:+y) = atan2 y x
34 instance (RealFloat a) => Num (Complex a) where
35 (x:+y) + (x':+y') = (x+x') :+ (y+y')
36 (x:+y) - (x':+y') = (x-x') :+ (y-y')
37 (x:+y) * (x':+y') = (x*x'-y*y') :+ (x*y'+y*x')
38 negate (x:+y) = negate x :+ negate y
39 abs z = magnitude z :+ 0
41 signum z@(x:+y) = x/r :+ y/r where r = magnitude z
42 fromInteger n = fromInteger n :+ 0
44 instance (RealFloat a) => Fractional (Complex a) where
45 (x:+y) / (x':+y') = (x*x''+y*y'') / d :+ (y*x''-x*y'') / d
46 where x'' = scaleFloat k x'
48 k = - max (exponent x') (exponent y')
51 fromRational a = fromRational a :+ 0
53 instance (RealFloat a) => Floating (Complex a) where
55 exp (x:+y) = expx * cos y :+ expx * sin y
57 log z = log (magnitude z) :+ phase z
60 sqrt z@(x:+y) = u :+ (if y < 0 then -v else v)
61 where (u,v) = if x < 0 then (v',u') else (u',v')
63 u' = sqrt ((magnitude z + abs x) / 2)
65 sin (x:+y) = sin x * cosh y :+ cos x * sinh y
66 cos (x:+y) = cos x * cosh y :+ (- sin x * sinh y)
67 tan (x:+y) = (sinx*coshy:+cosx*sinhy)/(cosx*coshy:+(-sinx*sinhy))
73 sinh (x:+y) = cos y * sinh x :+ sin y * cosh x
74 cosh (x:+y) = cos y * cosh x :+ sin y * sinh x
75 tanh (x:+y) = (cosy*sinhx:+siny*coshx)/(cosy*coshx:+siny*sinhx)
81 asin z@(x:+y) = y':+(-x')
82 where (x':+y') = log ((-y:+x) + sqrt (1 - z*z))
83 acos z@(x:+y) = y'':+(-x'')
84 where (x'':+y'') = log (z + ((-y'):+x'))
85 (x':+y') = sqrt (1 - z*z)
86 atan z@(x:+y) = y':+(-x')
87 where (x':+y') = log (((1-y):+x) / sqrt (1+z*z))
89 asinh z = log (z + sqrt (1+z*z))
90 acosh z = log (z + (z+1) * sqrt ((z-1)/(z+1)))
91 atanh z = log ((1+z) / sqrt (1-z*z))