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authorArne Döring <arne.doering@gmx.net>2018-11-05 20:27:46 +0100
committerAndreas Rumpf <rumpf_a@web.de>2018-11-05 20:27:46 +0100
commitcc5b8c6ad25b2db62274ca8fa76c4a5b3e794515 (patch)
treed107983330e5b6020899b437096b7f0513c64671 /lib
parentda178e4090ca63396c05e656abae76974263be83 (diff)
downloadNim-cc5b8c6ad25b2db62274ca8fa76c4a5b3e794515.tar.gz
Generic Complex type (#9590)
* remove `**`
* const `im` can now be used with Complex64
* converters from float|int to Complex are replaced by procs
* converters between various Complex types must stay to allow usage
of `im` with Complex64
* limit types for `+`, `-`, `/`, and `*` between Complex and float
* add `pow` for Complex and a number
* complex type changes
* unpublish approximation function
Diffstat (limited to 'lib')
-rw-r--r--lib/pure/complex.nim646
1 files changed, 329 insertions, 317 deletions
diff --git a/lib/pure/complex.nim b/lib/pure/complex.nim
index ba5c571ce..8c191f731 100644
--- a/lib/pure/complex.nim
+++ b/lib/pure/complex.nim
@@ -9,78 +9,109 @@
 
 
 
-## This module implements complex numbers.
-{.push checks:off, line_dir:off, stack_trace:off, debugger:off.}
-# the user does not want to trace a part
-# of the standard library!
 
 
-import
-  math
+## This module implements complex numbers.
+## Complex numbers are currently implemented as generic on a 64-bit or 32-bit float.
+
+{.push checks: off, line_dir: off, stack_trace: off, debugger: off.}
+# the user does not want to trace a part of the standard library!
 
-const
-  EPS = 1.0e-7 ## Epsilon used for float comparisons.
+import math
 
 type
-  Complex* = tuple[re, im: float]
-    ## a complex number, consisting of a real and an imaginary part
-
-const
-  im*: Complex = (re: 0.0, im: 1.0)
-    ## The imaginary unit. √-1.
+  Complex*[T: SomeFloat] = object
+    re, im: T
+    ## A complex number, consisting of a real and an imaginary part.
+  Complex64* = Complex[float64]
+    ## Alias for a pair of 64-bit floats.
+  Complex32* = Complex[float32]
+    ## Alias for a pair of 32-bit floats.
+
+proc complex*[T: SomeFloat](re: T; im: T = 0.0): Complex[T] =
+  result.re = re
+  result.im = im
+
+proc complex32*(re: float32; im: float32 = 0.0): Complex[float32] =
+  result.re = re
+  result.im = im
+
+proc complex64*(re: float64; im: float64 = 0.0): Complex[float64] =
+  result.re = re
+  result.im = im
+
+template im*(arg: typedesc[float32]): Complex32 = complex[float32](0, 1)
+template im*(arg: typedesc[float64]): Complex64 = complex[float64](0, 1)
+template im*(arg : float32): Complex32 = complex[float32](0, arg)
+template im*(arg : float64): Complex64 = complex[float64](0, arg)
+
+proc abs*[T](z: Complex[T]): T =
+  ## Return the distance from (0,0) to ``z``.
+  result = hypot(z.re, z.im)
+
+proc abs2*[T](z: Complex[T]): T =
+  ## Return the squared distance from (0,0) to ``z``.
+  result = z.re*z.re + z.im*z.im
+
+proc conjugate*[T](z: Complex[T]): Complex[T] =
+  ## Conjugate of complex number ``z``.
+  result.re = z.re
+  result.im = -z.im
 
-proc toComplex*(x: SomeInteger): Complex =
-  ## Convert some integer ``x`` to a complex number.
-  result.re = x
-  result.im = 0
+proc inv*[T](z: Complex[T]): Complex[T] =
+  ## Multiplicative inverse of complex number ``z``.
+  conjugate(z) / abs2(z)
 
-proc `==` *(x, y: Complex): bool =
-  ## Compare two complex numbers `x` and `y` for equality.
+proc `==` *[T](x, y: Complex[T]): bool =
+  ## Compare two complex numbers ``x`` and ``y`` for equality.
   result = x.re == y.re and x.im == y.im
 
-proc `=~` *(x, y: Complex): bool =
-  ## Compare two complex numbers `x` and `y` approximately.
-  result = abs(x.re-y.re)<EPS and abs(x.im-y.im)<EPS
-
-proc `+` *(x, y: Complex): Complex =
-  ## Add two complex numbers.
-  result.re = x.re + y.re
-  result.im = x.im + y.im
+proc `+` *[T](x: T, y: Complex[T]): Complex[T] =
+  ## Add a real number to a complex number.
+  result.re = x + y.re
+  result.im = y.im
 
-proc `+` *(x: Complex, y: float): Complex =
-  ## Add complex `x` to float `y`.
+proc `+` *[T](x: Complex[T], y: T): Complex[T] =
+  ## Add a complex number to a real number.
   result.re = x.re + y
   result.im = x.im
 
-proc `+` *(x: float, y: Complex): Complex =
-  ## Add float `x` to complex `y`.
-  result.re = x + y.re
-  result.im = y.im
-
+proc `+` *[T](x, y: Complex[T]): Complex[T] =
+  ## Add two complex numbers.
+  result.re = x.re + y.re
+  result.im = x.im + y.im
 
-proc `-` *(z: Complex): Complex =
+proc `-` *[T](z: Complex[T]): Complex[T] =
   ## Unary minus for complex numbers.
   result.re = -z.re
   result.im = -z.im
 
-proc `-` *(x, y: Complex): Complex =
+proc `-` *[T](x: T, y: Complex[T]): Complex[T] =
+  ## Subtract a complex number from a real number.
+  x + (-y)
+
+proc `-` *[T](x: Complex[T], y: T): Complex[T] =
+  ## Subtract a real number from a complex number.
+  result.re = x.re - y
+  result.im = x.im
+
+proc `-` *[T](x, y: Complex[T]): Complex[T] =
   ## Subtract two complex numbers.
   result.re = x.re - y.re
   result.im = x.im - y.im
 
-proc `-` *(x: Complex, y: float): Complex =
-  ## Subtracts float `y` from complex `x`.
-  result = x + (-y)
-
-proc `-` *(x: float, y: Complex): Complex =
-  ## Subtracts complex `y` from float `x`.
-  result = x + (-y)
+proc `/` *[T](x: Complex[T], y: T): Complex[T] =
+  ## Divide complex number ``x`` by real number ``y``.
+  result.re = x.re / y
+  result.im = x.im / y
 
+proc `/` *[T](x: T, y: Complex[T]): Complex[T] =
+  ## Divide real number ``x`` by complex number ``y``.
+  result = x * inv(y)
 
-proc `/` *(x, y: Complex): Complex =
-  ## Divide `x` by `y`.
-  var
-    r, den: float
+proc `/` *[T](x, y: Complex[T]): Complex[T] =
+  ## Divide ``x`` by ``y``.
+  var r, den: T
   if abs(y.re) < abs(y.im):
     r = y.re / y.im
     den = y.im + r * y.re
@@ -92,101 +123,46 @@ proc `/` *(x, y: Complex): Complex =
     result.re = (x.re + r * x.im) / den
     result.im = (x.im - r * x.re) / den
 
-proc `/` *(x : Complex, y: float ): Complex =
-  ## Divide complex `x` by float `y`.
-  result.re = x.re/y
-  result.im = x.im/y
-
-proc `/` *(x : float, y: Complex ): Complex =
-  ## Divide float `x` by complex `y`.
-  var num : Complex = (x, 0.0)
-  result = num/y
-
-
-proc `*` *(x, y: Complex): Complex =
-  ## Multiply `x` with `y`.
-  result.re = x.re * y.re - x.im * y.im
-  result.im = x.im * y.re + x.re * y.im
-
-proc `*` *(x: float, y: Complex): Complex =
-  ## Multiply float `x` with complex `y`.
+proc `*` *[T](x: T, y: Complex[T]): Complex[T] =
+  ## Multiply a real number and a complex number.
   result.re = x * y.re
   result.im = x * y.im
 
-proc `*` *(x: Complex, y: float): Complex =
-  ## Multiply complex `x` with float `y`.
+proc `*` *[T](x: Complex[T], y: T): Complex[T] =
+  ## Multiply a complex number with a real number.
   result.re = x.re * y
   result.im = x.im * y
 
+proc `*` *[T](x, y: Complex[T]): Complex[T] =
+  ## Multiply ``x`` with ``y``.
+  result.re = x.re * y.re - x.im * y.im
+  result.im = x.im * y.re + x.re * y.im
 
-proc `+=` *(x: var Complex, y: Complex) =
-  ## Add `y` to `x`.
+
+proc `+=` *[T](x: var Complex[T], y: Complex[T]) =
+  ## Add ``y`` to ``x``.
   x.re += y.re
   x.im += y.im
 
-proc `+=` *(x: var Complex, y: float) =
-  ## Add `y` to the complex number `x`.
-  x.re += y
-
-proc `-=` *(x: var Complex, y: Complex) =
-  ## Subtract `y` from `x`.
+proc `-=` *[T](x: var Complex[T], y: Complex[T]) =
+  ## Subtract ``y`` from ``x``.
   x.re -= y.re
   x.im -= y.im
 
-proc `-=` *(x: var Complex, y: float) =
-  ## Subtract `y` from the complex number `x`.
-  x.re -= y
-
-proc `*=` *(x: var Complex, y: Complex) =
-  ## Multiply `y` to `x`.
+proc `*=` *[T](x: var Complex[T], y: Complex[T]) =
+  ## Multiply ``y`` to ``x``.
   let im = x.im * y.re + x.re * y.im
   x.re = x.re * y.re - x.im * y.im
   x.im = im
 
-proc `*=` *(x: var Complex, y: float) =
-  ## Multiply `y` to the complex number `x`.
-  x.re *= y
-  x.im *= y
-
-proc `/=` *(x: var Complex, y: Complex) =
-  ## Divide `x` by `y` in place.
+proc `/=` *[T](x: var Complex[T], y: Complex[T]) =
+  ## Divide ``x`` by ``y`` in place.
   x = x / y
 
-proc `/=` *(x : var Complex, y: float) =
-  ## Divide complex `x` by float `y` in place.
-  x.re /= y
-  x.im /= y
-
-
-proc abs*(z: Complex): float =
-  ## Return the distance from (0,0) to `z`.
 
-  # optimized by checking special cases (sqrt is expensive)
-  var x, y, temp: float
-
-  x = abs(z.re)
-  y = abs(z.im)
-  if x == 0.0:
-    result = y
-  elif y == 0.0:
-    result = x
-  elif x > y:
-    temp = y / x
-    result = x * sqrt(1.0 + temp * temp)
-  else:
-    temp = x / y
-    result = y * sqrt(1.0 + temp * temp)
-
-
-proc conjugate*(z: Complex): Complex =
-  ## Conjugate of complex number `z`.
-  result.re = z.re
-  result.im = -z.im
-
-
-proc sqrt*(z: Complex): Complex =
-  ## Square root for a complex number `z`.
-  var x, y, w, r: float
+proc sqrt*[T](z: Complex[T]): Complex[T] =
+  ## Square root for a complex number ``z``.
+  var x, y, w, r: T
 
   if z.re == 0.0 and z.im == 0.0:
     result = z
@@ -199,247 +175,283 @@ proc sqrt*(z: Complex): Complex =
     else:
       r = x / y
       w = sqrt(y) * sqrt(0.5 * (r + sqrt(1.0 + r * r)))
+
     if z.re >= 0.0:
       result.re = w
       result.im = z.im / (w * 2.0)
     else:
-      if z.im >= 0.0: result.im = w
-      else:           result.im = -w
+      result.im = if z.im >= 0.0: w else: -w
       result.re = z.im / (result.im + result.im)
 
+proc exp*[T](z: Complex[T]): Complex[T] =
+  ## ``e`` raised to the power ``z``.
+  var
+    rho = exp(z.re)
+    theta = z.im
+  result.re = rho * cos(theta)
+  result.im = rho * sin(theta)
 
-proc exp*(z: Complex): Complex =
-  ## e raised to the power `z`.
-  var rho   = exp(z.re)
-  var theta = z.im
-  result.re = rho*cos(theta)
-  result.im = rho*sin(theta)
-
-
-proc ln*(z: Complex): Complex =
-  ## Returns the natural log of `z`.
+proc ln*[T](z: Complex[T]): Complex[T] =
+  ## Returns the natural log of ``z``.
   result.re = ln(abs(z))
-  result.im = arctan2(z.im,z.re)
-
-proc log10*(z: Complex): Complex =
-  ## Returns the log base 10 of `z`.
-  result = ln(z)/ln(10.0)
+  result.im = arctan2(z.im, z.re)
 
-proc log2*(z: Complex): Complex =
-  ## Returns the log base 2 of `z`.
-  result = ln(z)/ln(2.0)
+proc log10*[T](z: Complex[T]): Complex[T] =
+  ## Returns the log base 10 of ``z``.
+  result = ln(z) / ln(10.0)
 
+proc log2*[T](z: Complex[T]): Complex[T] =
+  ## Returns the log base 2 of ``z``.
+  result = ln(z) / ln(2.0)
 
-proc pow*(x, y: Complex): Complex =
-  ## `x` raised to the power `y`.
-  if x.re == 0.0  and  x.im == 0.0:
-    if y.re == 0.0  and  y.im == 0.0:
+proc pow*[T](x, y: Complex[T]): Complex[T] =
+  ## ``x`` raised to the power ``y``.
+  if x.re == 0.0 and x.im == 0.0:
+    if y.re == 0.0 and y.im == 0.0:
       result.re = 1.0
       result.im = 0.0
     else:
       result.re = 0.0
       result.im = 0.0
-  elif y.re == 1.0  and  y.im == 0.0:
+  elif y.re == 1.0 and y.im == 0.0:
     result = x
-  elif y.re == -1.0  and  y.im == 0.0:
-    result = 1.0/x
+  elif y.re == -1.0 and y.im == 0.0:
+    result = T(1.0) / x
   else:
-    var rho   = sqrt(x.re*x.re + x.im*x.im)
-    var theta = arctan2(x.im,x.re)
-    var s     = pow(rho,y.re) * exp(-y.im*theta)
-    var r     = y.re*theta + y.im*ln(rho)
-    result.re = s*cos(r)
-    result.im = s*sin(r)
-
-
-proc sin*(z: Complex): Complex =
-  ## Returns the sine of `z`.
-  result.re = sin(z.re)*cosh(z.im)
-  result.im = cos(z.re)*sinh(z.im)
-
-proc arcsin*(z: Complex): Complex =
-  ## Returns the inverse sine of `z`.
-  var i: Complex = (0.0,1.0)
-  result = -i*ln(i*z + sqrt(1.0-z*z))
-
-proc cos*(z: Complex): Complex =
-  ## Returns the cosine of `z`.
-  result.re = cos(z.re)*cosh(z.im)
-  result.im = -sin(z.re)*sinh(z.im)
-
-proc arccos*(z: Complex): Complex =
-  ## Returns the inverse cosine of `z`.
-  var i: Complex = (0.0,1.0)
-  result = -i*ln(z + sqrt(z*z-1.0))
-
-proc tan*(z: Complex): Complex =
-  ## Returns the tangent of `z`.
-  result = sin(z)/cos(z)
-
-proc arctan*(z: Complex): Complex =
-  ## Returns the inverse tangent of `z`.
-  var i: Complex = (0.0,1.0)
-  result = 0.5*i*(ln(1-i*z)-ln(1+i*z))
-
-proc cot*(z: Complex): Complex =
-  ## Returns the cotangent of `z`.
+    var
+      rho = abs(x)
+      theta = arctan2(x.im, x.re)
+      s = pow(rho, y.re) * exp(-y.im * theta)
+      r = y.re * theta + y.im * ln(rho)
+    result.re = s * cos(r)
+    result.im = s * sin(r)
+
+proc pow*[T](x: Complex[T], y: T): Complex[T] =
+  ## Complex number ``x`` raised to the power ``y``.
+  pow(x, complex[T](y))
+
+
+proc sin*[T](z: Complex[T]): Complex[T] =
+  ## Returns the sine of ``z``.
+  result.re = sin(z.re) * cosh(z.im)
+  result.im = cos(z.re) * sinh(z.im)
+
+proc arcsin*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse sine of ``z``.
+  result = -im(T) * ln(im(T) * z + sqrt(T(1.0) - z*z))
+
+proc cos*[T](z: Complex[T]): Complex[T] =
+  ## Returns the cosine of ``z``.
+  result.re = cos(z.re) * cosh(z.im)
+  result.im = -sin(z.re) * sinh(z.im)
+
+proc arccos*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse cosine of ``z``.
+  result = -im(T) * ln(z + sqrt(z*z - T(1.0)))
+
+proc tan*[T](z: Complex[T]): Complex[T] =
+  ## Returns the tangent of ``z``.
+  result = sin(z) / cos(z)
+
+proc arctan*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse tangent of ``z``.
+  result = T(0.5)*im(T) * (ln(T(1.0) - im(T)*z) - ln(T(1.0) + im(T)*z))
+
+proc cot*[T](z: Complex[T]): Complex[T] =
+  ## Returns the cotangent of ``z``.
   result = cos(z)/sin(z)
 
-proc arccot*(z: Complex): Complex =
-  ## Returns the inverse cotangent of `z`.
-  var i: Complex = (0.0,1.0)
-  result = 0.5*i*(ln(1-i/z)-ln(1+i/z))
+proc arccot*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse cotangent of ``z``.
+  result = T(0.5)*im(T) * (ln(T(1.0) - im(T)/z) - ln(T(1.0) + im(T)/z))
 
-proc sec*(z: Complex): Complex =
-  ## Returns the secant of `z`.
-  result = 1.0/cos(z)
+proc sec*[T](z: Complex[T]): Complex[T] =
+  ## Returns the secant of ``z``.
+  result = T(1.0) / cos(z)
 
-proc arcsec*(z: Complex): Complex =
-  ## Returns the inverse secant of `z`.
-  var i: Complex = (0.0,1.0)
-  result = -i*ln(i*sqrt(1-1/(z*z))+1/z)
+proc arcsec*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse secant of ``z``.
+  result = -im(T) * ln(im(T) * sqrt(1.0 - 1.0/(z*z)) + T(1.0)/z)
 
-proc csc*(z: Complex): Complex =
-  ## Returns the cosecant of `z`.
-  result = 1.0/sin(z)
+proc csc*[T](z: Complex[T]): Complex[T] =
+  ## Returns the cosecant of ``z``.
+  result = T(1.0) / sin(z)
 
-proc arccsc*(z: Complex): Complex =
-  ## Returns the inverse cosecant of `z`.
-  var i: Complex = (0.0,1.0)
-  result = -i*ln(sqrt(1-1/(z*z))+i/z)
+proc arccsc*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse cosecant of ``z``.
+  result = -im(T) * ln(sqrt(T(1.0) - T(1.0)/(z*z)) + im(T)/z)
 
+proc sinh*[T](z: Complex[T]): Complex[T] =
+  ## Returns the hyperbolic sine of ``z``.
+  result = T(0.5) * (exp(z) - exp(-z))
 
-proc sinh*(z: Complex): Complex =
-  ## Returns the hyperbolic sine of `z`.
-  result = 0.5*(exp(z)-exp(-z))
+proc arcsinh*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse hyperbolic sine of ``z``.
+  result = ln(z + sqrt(z*z + 1.0))
 
-proc arcsinh*(z: Complex): Complex =
-  ## Returns the inverse hyperbolic sine of `z`.
-  result = ln(z+sqrt(z*z+1))
+proc cosh*[T](z: Complex[T]): Complex[T] =
+  ## Returns the hyperbolic cosine of ``z``.
+  result = T(0.5) * (exp(z) + exp(-z))
 
-proc cosh*(z: Complex): Complex =
-  ## Returns the hyperbolic cosine of `z`.
-  result = 0.5*(exp(z)+exp(-z))
+proc arccosh*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse hyperbolic cosine of ``z``.
+  result = ln(z + sqrt(z*z - T(1.0)))
 
-proc arccosh*(z: Complex): Complex =
-  ## Returns the inverse hyperbolic cosine of `z`.
-  result = ln(z+sqrt(z*z-1))
+proc tanh*[T](z: Complex[T]): Complex[T] =
+  ## Returns the hyperbolic tangent of ``z``.
+  result = sinh(z) / cosh(z)
 
-proc tanh*(z: Complex): Complex =
-  ## Returns the hyperbolic tangent of `z`.
-  result = sinh(z)/cosh(z)
+proc arctanh*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse hyperbolic tangent of ``z``.
+  result = T(0.5) * (ln((T(1.0)+z) / (T(1.0)-z)))
 
-proc arctanh*(z: Complex): Complex =
-  ## Returns the inverse hyperbolic tangent of `z`.
-  result = 0.5*(ln((1+z)/(1-z)))
+proc sech*[T](z: Complex[T]): Complex[T] =
+  ## Returns the hyperbolic secant of ``z``.
+  result = T(2.0) / (exp(z) + exp(-z))
 
-proc sech*(z: Complex): Complex =
-  ## Returns the hyperbolic secant of `z`.
-  result = 2/(exp(z)+exp(-z))
+proc arcsech*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse hyperbolic secant of ``z``.
+  result = ln(1.0/z + sqrt(T(1.0)/z+T(1.0)) * sqrt(T(1.0)/z-T(1.0)))
 
-proc arcsech*(z: Complex): Complex =
-  ## Returns the inverse hyperbolic secant of `z`.
-  result = ln(1/z+sqrt(1/z+1)*sqrt(1/z-1))
+proc csch*[T](z: Complex[T]): Complex[T] =
+  ## Returns the hyperbolic cosecant of ``z``.
+  result = T(2.0) / (exp(z) - exp(-z))
 
-proc csch*(z: Complex): Complex =
-  ## Returns the hyperbolic cosecant of `z`.
-  result = 2/(exp(z)-exp(-z))
+proc arccsch*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse hyperbolic cosecant of ``z``.
+  result = ln(T(1.0)/z + sqrt(T(1.0)/(z*z) + T(1.0)))
 
-proc arccsch*(z: Complex): Complex =
-  ## Returns the inverse hyperbolic cosecant of `z`.
-  result = ln(1/z+sqrt(1/(z*z)+1))
+proc coth*[T](z: Complex[T]): Complex[T] =
+  ## Returns the hyperbolic cotangent of ``z``.
+  result = cosh(z) / sinh(z)
 
-proc coth*(z: Complex): Complex =
-  ## Returns the hyperbolic cotangent of `z`.
-  result = cosh(z)/sinh(z)
+proc arccoth*[T](z: Complex[T]): Complex[T] =
+  ## Returns the inverse hyperbolic cotangent of ``z``.
+  result = T(0.5) * (ln(T(1.0) + T(1.0)/z) - ln(T(1.0) - T(1.0)/z))
 
-proc arccoth*(z: Complex): Complex =
-  ## Returns the inverse hyperbolic cotangent of `z`.
-  result = 0.5*(ln(1+1/z)-ln(1-1/z))
-
-proc phase*(z: Complex): float =
-  ## Returns the phase of `z`.
+proc phase*[T](z: Complex[T]): T =
+  ## Returns the phase of ``z``.
   arctan2(z.im, z.re)
 
-proc polar*(z: Complex): tuple[r, phi: float] =
-  ## Returns `z` in polar coordinates.
-  result.r = abs(z)
-  result.phi = phase(z)
+proc polar*[T](z: Complex[T]): tuple[r, phi: T] =
+  ## Returns ``z`` in polar coordinates.
+  (r: abs(z), phi: phase(z))
 
-proc rect*(r: float, phi: float): Complex =
-  ## Returns the complex number with polar coordinates `r` and `phi`.
-  result.re = r * cos(phi)
-  result.im = r * sin(phi)
+proc rect*[T](r, phi: T): Complex[T] =
+  ## Returns the complex number with polar coordinates ``r`` and ``phi``.
+  ##
+  ## | ``result.re = r * cos(phi)``
+  ## | ``result.im = r * sin(phi)``
+  complex(r * cos(phi), r * sin(phi))
 
 
 proc `$`*(z: Complex): string =
-  ## Returns `z`'s string representation as ``"(re, im)"``.
+  ## Returns ``z``'s string representation as ``"(re, im)"``.
   result = "(" & $z.re & ", " & $z.im & ")"
 
 {.pop.}
 
 
 when isMainModule:
-  var z = (0.0, 0.0)
-  var oo = (1.0,1.0)
-  var a = (1.0, 2.0)
-  var b = (-1.0, -2.0)
-  var m1 = (-1.0, 0.0)
-  var i = (0.0,1.0)
-  var one = (1.0,0.0)
-  var tt = (10.0, 20.0)
-  var ipi = (0.0, -PI)
-
-  assert( a == a )
-  assert( (a-a) == z )
-  assert( (a+b) == z )
-  assert( (a/b) == m1 )
-  assert( (1.0/a) == (0.2, -0.4) )
-  assert( (a*b) == (3.0, -4.0) )
-  assert( 10.0*a == tt )
-  assert( a*10.0 == tt )
-  assert( tt/10.0 == a )
-  assert( oo+(-1.0) == i )
-  assert( (-1.0)+oo == i )
-  assert( abs(oo) == sqrt(2.0) )
-  assert( conjugate(a) == (1.0, -2.0) )
-  assert( sqrt(m1) == i )
-  assert( exp(ipi) =~ m1 )
-
-  assert( pow(a,b) =~ (-3.72999124927876, -1.68815826725068) )
-  assert( pow(z,a) =~ (0.0, 0.0) )
-  assert( pow(z,z) =~ (1.0, 0.0) )
-  assert( pow(a,one) =~ a )
-  assert( pow(a,m1) =~ (0.2, -0.4) )
-
-  assert( ln(a) =~ (0.804718956217050, 1.107148717794090) )
-  assert( log10(a) =~ (0.349485002168009, 0.480828578784234) )
-  assert( log2(a) =~ (1.16096404744368, 1.59727796468811) )
-
-  assert( sin(a) =~ (3.16577851321617, 1.95960104142161) )
-  assert( cos(a) =~ (2.03272300701967, -3.05189779915180) )
-  assert( tan(a) =~ (0.0338128260798967, 1.0147936161466335) )
-  assert( cot(a) =~ 1.0/tan(a) )
-  assert( sec(a) =~ 1.0/cos(a) )
-  assert( csc(a) =~ 1.0/sin(a) )
-  assert( arcsin(a) =~ (0.427078586392476, 1.528570919480998) )
-  assert( arccos(a) =~ (1.14371774040242, -1.52857091948100) )
-  assert( arctan(a) =~ (1.338972522294494, 0.402359478108525) )
-
-  assert( cosh(a) =~ (-0.642148124715520, 1.068607421382778) )
-  assert( sinh(a) =~ (-0.489056259041294, 1.403119250622040) )
-  assert( tanh(a) =~ (1.1667362572409199,-0.243458201185725) )
-  assert( sech(a) =~ 1/cosh(a) )
-  assert( csch(a) =~ 1/sinh(a) )
-  assert( coth(a) =~ 1/tanh(a) )
-  assert( arccosh(a) =~ (1.528570919480998, 1.14371774040242) )
-  assert( arcsinh(a) =~ (1.469351744368185, 1.06344002357775) )
-  assert( arctanh(a) =~ (0.173286795139986, 1.17809724509617) )
-  assert( arcsech(a) =~ arccosh(1/a) )
-  assert( arccsch(a) =~ arcsinh(1/a) )
-  assert( arccoth(a) =~ arctanh(1/a) )
-
-  assert( phase(a) == 1.1071487177940904 )
+  proc `=~`[T](x, y: Complex[T]): bool =
+    result = abs(x.re-y.re) < 1e-6 and abs(x.im-y.im) < 1e-6
+
+  proc `=~`[T](x: Complex[T], y: T): bool =
+    result = abs(x.re-y) < 1e-6 and abs(x.im) < 1e-6
+
+  var
+    z: Complex64   = complex(0.0, 0.0)
+    oo: Complex64  = complex(1.0, 1.0)
+    a: Complex64   = complex(1.0, 2.0)
+    b: Complex64   = complex(-1.0, -2.0)
+    m1: Complex64  = complex(-1.0, 0.0)
+    i: Complex64   = complex(0.0, 1.0)
+    one: Complex64 = complex(1.0, 0.0)
+    tt: Complex64  = complex(10.0, 20.0)
+    ipi: Complex64 = complex(0.0, -PI)
+
+  doAssert(a/2.0 =~ complex(0.5, 1.0))
+  doAssert(a == a)
+  doAssert((a-a) == z)
+  doAssert((a+b) == z)
+  doAssert((a+b) =~ 0.0)
+  doAssert((a/b) == m1)
+  doAssert((1.0/a) == complex(0.2, -0.4))
+  doAssert((a*b) == complex(3.0, -4.0))
+  doAssert(10.0*a == tt)
+  doAssert(a*10.0 == tt)
+  doAssert(tt/10.0 == a)
+  doAssert(oo+(-1.0) == i)
+  doAssert( (-1.0)+oo == i)
+  doAssert(abs(oo) == sqrt(2.0))
+  doAssert(conjugate(a) == complex(1.0, -2.0))
+  doAssert(sqrt(m1) == i)
+  doAssert(exp(ipi) =~ m1)
+
+  doAssert(pow(a, b) =~ complex(-3.72999124927876, -1.68815826725068))
+  doAssert(pow(z, a) =~ complex(0.0, 0.0))
+  doAssert(pow(z, z) =~ complex(1.0, 0.0))
+  doAssert(pow(a, one) =~ a)
+  doAssert(pow(a, m1) =~ complex(0.2, -0.4))
+  doAssert(pow(a, 2.0) =~ complex(-3.0, 4.0))
+  doAssert(pow(a, 2) =~ complex(-3.0, 4.0))
+  doAssert(not(pow(a, 2.0) =~ a))
+
+  doAssert(ln(a) =~ complex(0.804718956217050, 1.107148717794090))
+  doAssert(log10(a) =~ complex(0.349485002168009, 0.480828578784234))
+  doAssert(log2(a) =~ complex(1.16096404744368, 1.59727796468811))
+
+  doAssert(sin(a) =~ complex(3.16577851321617, 1.95960104142161))
+  doAssert(cos(a) =~ complex(2.03272300701967, -3.05189779915180))
+  doAssert(tan(a) =~ complex(0.0338128260798967, 1.0147936161466335))
+  doAssert(cot(a) =~ 1.0 / tan(a))
+  doAssert(sec(a) =~ 1.0 / cos(a))
+  doAssert(csc(a) =~ 1.0 / sin(a))
+  doAssert(arcsin(a) =~ complex(0.427078586392476, 1.528570919480998))
+  doAssert(arccos(a) =~ complex(1.14371774040242, -1.52857091948100))
+  doAssert(arctan(a) =~ complex(1.338972522294494, 0.402359478108525))
+  doAssert(arccot(a) =~ complex(0.2318238045004031, -0.402359478108525))
+  doAssert(arcsec(a) =~ complex(1.384478272687081, 0.3965682301123288))
+  doAssert(arccsc(a) =~ complex(0.1863180541078155, -0.3965682301123291))
+
+  doAssert(cosh(a) =~ complex(-0.642148124715520, 1.068607421382778))
+  doAssert(sinh(a) =~ complex(-0.489056259041294, 1.403119250622040))
+  doAssert(tanh(a) =~ complex(1.1667362572409199, -0.243458201185725))
+  doAssert(sech(a) =~ 1.0 / cosh(a))
+  doAssert(csch(a) =~ 1.0 / sinh(a))
+  doAssert(coth(a) =~ 1.0 / tanh(a))
+  doAssert(arccosh(a) =~ complex(1.528570919480998, 1.14371774040242))
+  doAssert(arcsinh(a) =~ complex(1.469351744368185, 1.06344002357775))
+  doAssert(arctanh(a) =~ complex(0.173286795139986, 1.17809724509617))
+  doAssert(arcsech(a) =~ arccosh(1.0/a))
+  doAssert(arccsch(a) =~ arcsinh(1.0/a))
+  doAssert(arccoth(a) =~ arctanh(1.0/a))
+
+  doAssert(phase(a) == 1.1071487177940904)
   var t = polar(a)
-  assert( rect(t.r, t.phi) =~ a )
-  assert( rect(1.0, 2.0) =~ (-0.4161468365471424, 0.9092974268256817) )
+  doAssert(rect(t.r, t.phi) =~ a)
+  doAssert(rect(1.0, 2.0) =~ complex(-0.4161468365471424, 0.9092974268256817))
+
+
+  var
+    i64: Complex32 = complex(0.0f, 1.0f)
+    a64: Complex32 = 2.0f*i64 + 1.0.float32
+    b64: Complex32 = complex(-1.0'f32, -2.0'f32)
+
+  doAssert(a64 == a64)
+  doAssert(a64 == -b64)
+  doAssert(a64 + b64 =~ 0.0'f32)
+  doAssert(not(pow(a64, b64) =~ a64))
+  doAssert(pow(a64, 0.5f) =~ sqrt(a64))
+  doAssert(pow(a64, 2) =~ complex(-3.0'f32, 4.0'f32))
+  doAssert(sin(arcsin(b64)) =~ b64)
+  doAssert(cosh(arccosh(a64)) =~ a64)
+
+  doAssert(phase(a64) - 1.107149f < 1e-6)
+  var t64 = polar(a64)
+  doAssert(rect(t64.r, t64.phi) =~ a64)
+  doAssert(rect(1.0f, 2.0f) =~ complex(-0.4161468f, 0.90929742f))
+  doAssert(sizeof(a64) == 8)
+  doAssert(sizeof(a) == 16)
+
+  doAssert 123.0.im + 456.0 == complex64(456, 123)