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class Complex { double _r,_i;
 Complex(this._r,this._i); double get r => _r; double get i => _i; String toString() => "($r,$i)";
 Complex operator +(Complex other) => new Complex(r+other.r,i+other.i); Complex operator *(Complex other) => new Complex(r*other.r-i*other.i,r*other.i+other.r*i); double abs() => r*r+i*i;}
void main() { double start_x=-1.5; double start_y=-1.0; double step_x=0.03; double step_y=0.1;
 for(int y=0;y<20;y++) { String line=""; for(int x=0;x<70;x++) { Complex c=new Complex(start_x+step_x*x,start_y+step_y*y); Complex z=new Complex(0.0, 0.0); for(int i=0;i<100;i++) { z=z*(z)+c; if(z.abs()>2) { break; } } line+=z.abs()>2 ? " " : "*"; } print(line); }}

defmodule Mandelbrot do def set do xsize = 59 ysize = 21 minIm = -1.0 maxIm = 1.0 minRe = -2.0 maxRe = 1.0 stepX = (maxRe - minRe) / xsize stepY = (maxIm - minIm) / ysize Enum.each(0..ysize, fn y -> im = minIm + stepY * y Enum.map(0..xsize, fn x -> re = minRe + stepX * x 62 - loop(0, re, im, re, im, re*re+im*im) end) |> IO.puts end) end
 defp loop(n, _, _, _, _, _) when n>=30, do: n defp loop(n, _, _, _, _, v) when v>4.0, do: n-1 defp loop(n, re, im, zr, zi, _) do a = zr * zr b = zi * zi loop(n+1, re, im, a-b+re, 2*zr*zi+im, a+b) endend
Mandelbrot.set

package main
import ( "fmt" "image" "image/color" "image/draw" "image/png" "math/cmplx" "os")
const ( maxEsc = 100 rMin = -2. rMax = .5 iMin = -1. iMax = 1. width = 750 red = 230 green = 235 blue = 255)
func mandelbrot(a complex128) float64 { i := 0 for z := a; cmplx.Abs(z) < 2 && i < maxEsc; i++ { z = z*z + a } return float64(maxEsc-i) / maxEsc}
func main() { scale := width / (rMax - rMin) height := int(scale * (iMax - iMin)) bounds := image.Rect(0, 0, width, height) b := image.NewNRGBA(bounds) draw.Draw(b, bounds, image.NewUniform(color.Black), image.ZP, draw.Src) for x := 0; x < width; x++ { for y := 0; y < height; y++ { fEsc := mandelbrot(complex( float64(x)/scale+rMin, float64(y)/scale+iMin)) b.Set(x, y, color.NRGBA{uint8(red * fEsc), uint8(green * fEsc), uint8(blue * fEsc), 255})
 } } f, err := os.Create("mandelbrot.png") if err != nil { fmt.Println(err) return } if err = png.Encode(f, b); err != nil { fmt.Println(err) } if err = f.Close(); err != nil { fmt.Println(err) }}

using Images
@inline function hsv2rgb(h, s, v) const c = v * s const x = c * (1 - abs(((h/60) % 2) - 1)) const m = v - c
 const r,g,b = if h < 60 (c, x, 0) elseif h < 120 (x, c, 0) elseif h < 180 (0, c, x) elseif h < 240 (0, x, c) elseif h < 300 (x, 0, c) else (c, 0, x) end
 (r + m), (b + m), (g + m)end
function mandelbrot()
 const w, h = 1000, 1000
 const zoom = 0.5 const moveX = 0 const moveY = 0
 const img = Array{RGB{Float64}}(h, w) const maxIter = 30
 for x in 1:w for y in 1:h i = maxIter const c = Complex( (2*x - w) / (w * zoom) + moveX, (2*y - h) / (h * zoom) + moveY ) z = c while abs(z) < 2 && (i -= 1) > 0 z = z^2 + c end const r,g,b = hsv2rgb(i / maxIter * 360, 1, i / maxIter) img[y,x] = RGB{Float64}(r, g, b) end end
 save("mandelbrot_set.png", img)end
mandelbrot()

import java.awt.Graphicsimport java.awt.image.BufferedImageimport javax.swing.JFrame
class Mandelbrot: JFrame("Mandelbrot Set") { companion object { private const val MAX_ITER = 570 private const val ZOOM = 150.0 }
 private val img: BufferedImage
 init { setBounds(100, 100, 800, 600) isResizable = false defaultCloseOperation = EXIT_ON_CLOSE img = BufferedImage(width, height, BufferedImage.TYPE_INT_RGB) for (y in 0 until height) { for (x in 0 until width) { var zx = 0.0 var zy = 0.0 val cX = (x - 400) / ZOOM val cY = (y - 300) / ZOOM var iter = MAX_ITER while (zx * zx + zy * zy < 4.0 && iter > 0) { val tmp = zx * zx - zy * zy + cX zy = 2.0 * zx * zy + cY zx = tmp iter-- } img.setRGB(x, y, iter or (iter shl 7)) } } }
 override fun paint(g: Graphics) { g.drawImage(img, 0, 0, this) }}
fun main(args: Array<String>) { Mandelbrot().isVisible = true}

local maxIterations = 250local minX, maxX, minY, maxY = -2.5, 2.5, -2.5, 2.5local miX, mxX, miY, mxYfunction remap( x, t1, t2, s1, s2 ) local f = ( x - t1 ) / ( t2 - t1 ) local g = f * ( s2 - s1 ) + s1 return g;endfunction drawMandelbrot() local pts, a, as, za, b, bs, zb, cnt, clr = {} for j = 0, hei - 1 do for i = 0, wid - 1 do a = remap( i, 0, wid, minX, maxX ) b = remap( j, 0, hei, minY, maxY ) cnt = 0; za = a; zb = b while( cnt < maxIterations ) do as = a * a - b * b; bs = 2 * a * b a = za + as; b = zb + bs if math.abs( a ) + math.abs( b ) > 16 then break end cnt = cnt + 1 end if cnt == maxIterations then clr = 0 else clr = remap( cnt, 0, maxIterations, 0, 255 ) end pts[1] = { i, j, clr, clr, 0, 255 } love.graphics.points( pts ) end endendfunction startFractal() love.graphics.setCanvas( canvas ); love.graphics.clear() love.graphics.setColor( 255, 255, 255 ) drawMandelbrot(); love.graphics.setCanvas()endfunction love.load() wid, hei = love.graphics.getWidth(), love.graphics.getHeight() canvas = love.graphics.newCanvas( wid, hei ) startFractal()endfunction love.mousepressed( x, y, button, istouch ) if button == 1 then startDrag = true; miX = x; miY = y else minX = -2.5; maxX = 2.5; minY = minX; maxY = maxX startFractal() startDrag = false endendfunction love.mousereleased( x, y, button, istouch ) if startDrag then local l if x > miX then mxX = x else l = x; mxX = miX; miX = l end if y > miY then mxY = y else l = y; mxY = miY; miY = l end miX = remap( miX, 0, wid, minX, maxX )  mxX = remap( mxX, 0, wid, minX, maxX ) miY = remap( miY, 0, hei, minY, maxY )  mxY = remap( mxY, 0, hei, minY, maxY ) minX = miX; maxX = mxX; minY = miY; maxY = mxY startFractal() endendfunction love.draw() love.graphics.draw( canvas )end

Object subclass: #FractalTree instanceVariableNames: '' classVariableNames: '' poolDictionaries: '' category: 'RosettaCode'
"Methods for FractalTree class"
tree: aPoint length: aLength angle: anAngle | p a |
 (aLength > 10) ifTrue: [ p := Pen new. p up. p goto: aPoint. p turn: anAngle. p down. 5 timesRepeat: [ p go: aLength / 5. p turn: 5. ]. a := anAngle - 30. 3 timesRepeat: [ self tree: p location length: aLength * 0.7 angle: a. a := a + 30. ] ].
draw Display restoreAfter: [ Display fillWhite.  self tree: 700@700 length: 200 angle: 0. ]
"Execute"
FractalTree new draw.

extern crate image;extern crate num_complex;
use std::fs::File;use num_complex::Complex;
fn main() { let max_iterations = 256u16; let img_side = 800u32; let cxmin = -2f32; let cxmax = 1f32; let cymin = -1.5f32; let cymax = 1.5f32; let scalex = (cxmax - cxmin) / img_side as f32; let scaley = (cymax - cymin) / img_side as f32;
 // Create a new ImgBuf let mut imgbuf = image::ImageBuffer::new(img_side, img_side);
 // Calculate for each pixel for (x, y, pixel) in imgbuf.enumerate_pixels_mut() { let cx = cxmin + x as f32 * scalex; let cy = cymin + y as f32 * scaley;
 let c = Complex::new(cx, cy); let mut z = Complex::new(0f32, 0f32);
 let mut i = 0; for t in 0..max_iterations { if z.norm() > 2.0 { break; } z = z * z + c; i = t; }
 *pixel = image::Luma([i as u8]); }
 // Save image let fout = &mut File::create("fractal.png").unwrap(); image::ImageLuma8(imgbuf).save(fout, image::PNG).unwrap();}

// Set up canvas for drawingvar canvas: HTMLCanvasElement = document.createElement('canvas')canvas.width = 600canvas.height = 500document.body.appendChild(canvas)var ctx: CanvasRenderingContext2D = canvas.getContext('2d')ctx.fillStyle = '#000'ctx.lineWidth = 1
// constantsconst degToRad: number = Math.PI / 180.0const totalDepth: number = 9
/** Helper function that draws a line on the canvas */function drawLine(x1: number, y1: number, x2: number, y2: number): void { ctx.moveTo(x1, y1) ctx.lineTo(x2, y2)}
/** Draws a branch at the given point and angle and then calls itself twice */function drawTree(x1: number, y1: number, angle: number, depth: number): void { if (depth !== 0) { let x2: number = x1 + (Math.cos(angle * degToRad) * depth * 10.0) let y2: number = y1 + (Math.sin(angle * degToRad) * depth * 10.0) drawLine(x1, y1, x2, y2) drawTree(x2, y2, angle - 20, depth - 1) drawTree(x2, y2, angle + 20, depth - 1) }}
// actual drawing of treectx.beginPath()drawTree(300, 500, -90, totalDepth)ctx.closePath()ctx.stroke()