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# bug #3799
import macros
const nmax = 500
type
Complex*[T] = object
re*: T
im*: T
converter toComplex*[T](x: tuple[re, im: T]): Complex[T] =
result.re = x.re
result.im = x.im
proc julia*[T](z0, c: Complex[T], er2: T, nmax: int): int =
result = 0
var z = z0
var sre = z0.re * z0.re
var sim = z0.im * z0.im
while (result < nmax) and (sre + sim < er2):
z.im = z.re * z.im
z.im = z.im + z.im
z.im = z.im + c.im
z.re = sre - sim + c.re
sre = z.re * z.re
sim = z.im * z.im
inc result
template dendriteFractal*[T](z0: Complex[T], er2: T, nmax: int): int =
julia(z0, (T(0.0), T(1.0)), er2, nmax)
iterator stepIt[T](start, step: T, iterations: int): T =
for i in 0 .. iterations:
yield start + T(i) * step
let c = (0.36237, 0.32)
for y in stepIt(2.0, -0.0375, 107):
var row = ""
for x in stepIt(-2.0, 0.025, 160):
#let n = julia((x, y), c, 4.0, nmax) ### this works
let n = dendriteFractal((x, y), 4.0, nmax)
if n < nmax:
row.add($(n mod 10))
else:
row.add(' ')
echo row
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