Archimedean spiral

From Rosetta Code
Task
Archimedean spiral
You are encouraged to solve this task according to the task description, using any language you may know.

The Archimedean spiral is a spiral named after the Greek mathematician Archimedes.


An Archimedean spiral can be described by the equation:

with real numbers a and b.


Task

Draw an Archimedean spiral.

Action!

Action! does not provide trigonometric functions. Therefore a simple implementation for Sin and Cos function has been provided.

INT ARRAY SinTab=[
  0 4 9 13 18 22 27 31 36 40 44 49 53 58 62 66 71 75 79 83
  88 92 96 100 104 108 112 116 120 124 128 132 136 139 143
  147 150 154 158 161 165 168 171 175 178 181 184 187 190
  193 196 199 202 204 207 210 212 215 217 219 222 224 226
  228 230 232 234 236 237 239 241 242 243 245 246 247 248
  249 250 251 252 253 254 254 255 255 255 256 256 256 256]

INT FUNC Sin(INT a)
  WHILE a<0 DO a==+360 OD
  WHILE a>360 DO a==-360 OD
  IF a<=90 THEN
    RETURN (SinTab(a))
  ELSEIF a<=180 THEN
    RETURN (SinTab(180-a))
  ELSEIF a<=270 THEN
    RETURN (-SinTab(a-180))
  ELSE
    RETURN (-SinTab(360-a))
  FI
RETURN (0)

INT FUNC Cos(INT a)
RETURN (Sin(a-90))

PROC DrawSpiral(INT x0,y0)
  INT angle,radius,x,y

  Plot(x0,y0)
  FOR angle=0 TO 1800 STEP 5
  DO
    radius=angle/20
    x=radius*Cos(angle)/256+x0
    y=radius*Sin(angle)/256+y0
    DrawTo(x,y)
  OD
RETURN

PROC Main()
  BYTE CH=$02FC,COLOR1=$02C5,COLOR2=$02C6

  Graphics(8+16)
  Color=1
  COLOR1=$0C
  COLOR2=$02

  DrawSpiral(160,96)

  DO UNTIL CH#$FF OD
  CH=$FF
RETURN
Output:

Screenshot from Atari 8-bit computer

Ada

Library: SDLAda
with Ada.Numerics.Elementary_Functions;

with SDL.Video.Windows.Makers;
with SDL.Video.Renderers.Makers;
with SDL.Events.Events;

procedure Archimedean_Spiral is

   Width      : constant := 800;
   Height     : constant := 800;
   A          : constant := 4.2;
   B          : constant := 3.2;
   T_First    : constant := 4.0;
   T_Last     : constant := 100.0;

   Window   : SDL.Video.Windows.Window;
   Renderer : SDL.Video.Renderers.Renderer;
   Event    : SDL.Events.Events.Events;

   procedure Draw_Archimedean_Spiral is
      use type SDL.C.int;
      use Ada.Numerics.Elementary_Functions;
      Pi   : constant := Ada.Numerics.Pi;
      Step : constant := 0.002;
      T    : Float;
      R    : Float;
   begin
      T := T_First;
      loop
         R := A + B * T;
         Renderer.Draw
           (Point => (X => Width  / 2 + SDL.C.int (R * Cos (T, 2.0 * Pi)),
                      Y => Height / 2 - SDL.C.int (R * Sin (T, 2.0 * Pi))));
         exit when T >= T_Last;
         T := T + Step;
      end loop;
   end Draw_Archimedean_Spiral;

   procedure Wait is
      use type SDL.Events.Event_Types;
   begin
      loop
         while SDL.Events.Events.Poll (Event) loop
            if Event.Common.Event_Type = SDL.Events.Quit then
               return;
            end if;
         end loop;
      end loop;
   end Wait;

begin
   if not SDL.Initialise (Flags => SDL.Enable_Screen) then
      return;
   end if;

   SDL.Video.Windows.Makers.Create (Win      => Window,
                                    Title    => "Archimedean spiral",
                                    Position => SDL.Natural_Coordinates'(X => 10, Y => 10),
                                    Size     => SDL.Positive_Sizes'(Width, Height),
                                    Flags    => 0);
   SDL.Video.Renderers.Makers.Create (Renderer, Window.Get_Surface);
   Renderer.Set_Draw_Colour ((0, 0, 0, 255));
   Renderer.Fill (Rectangle => (0, 0, Width, Height));
   Renderer.Set_Draw_Colour ((0, 220, 0, 255));

   Draw_Archimedean_Spiral;
   Window.Update_Surface;

   Wait;
   Window.Finalize;
   SDL.Finalise;
end Archimedean_Spiral;

ALGOL W

Translation of: AWK

This version doubles the characters horiontally to give a slightly more rounded shape.

begin % draw an Archimedian spiral %
      % Translation of AWK which was a trnslation of Applesoft Basic program %
    integer procedure max ( integer x, y ) ; begin if x > y then x else y end;
    integer procedure min ( integer x, y ) ; begin if x < y then x else y end;
    integer x_min, y_min, x_max, y_max, a, b, x, y;
    string(255) array arr ( 1 :: 255 );
    real    h, w, m, s, t;
    x_min := y_min := 9999;
    x_max := y_max := 0;
    h := 96;
    w := h + h / 2;
    a := 1;
    b := 1;
    m := 6 * PI;
    s := .02;
    t := s;
    while t <= m do begin % build spiral %
      real r;
      r := a + b * t;
      x := round(r * cos(t) + w);
      y := round(r * sin(t) + h);
      if x <= 0 or y <= 0 then begin end
      else if x >= 280    then begin end
      else if y >= 192    then begin end
      else begin
        arr( x )( y // 1 ) := "*";
        x_min := min(x_min,x);
        x_max := max(x_max,x);
        y_min := min(y_min,y);
        y_max := max(y_max,y);
        t     := t + s
      end if__various_x_and_y_values__
    end while__t_le_m ;
    for i := x_min until x_max do begin
        for j := y_min until y_max do begin
            string(1) c;
            c := arr( i )( j // 1 );
            writeon( c, c )
        end for_j ;
        write()
    end for_i
end.
Output:
                            **************
                      ********          ********
                  ******                        ****
              ****                                ******
            ****                                      ****
          ****                                          ****
        ****                                              ****
      ****                ******************                **
    ****              ****                ******              **
    **              ****                      ****            ****
  ****            **                            ****            **
  **            ****                              ****          **
  **          ****                                  **            **
**            **              **********            ****          **
**          ****          ****        ****            **          **
**          **            **            ****          **          **
**          **          ****              **          **          **
**          **          **              ****          **          **
**          **          **          ******            **          **
**          **          **                          ****          **
**          **          ****                        **            **
**          **            **                      ****          **
**            **          ****                  ****            **
**            **            ******            ****            ****
  **          ****              **************                **
  **            **                                          **
  ****            **                                      ****
    **            ****                                  ****
    ****              ****                          ******
      **                ******                  ******
        **                  ********      ********
          **                      **********
            **
              ****
                ******
                    ******
                        ********
                              ********

Amazing Hopper

Translation of: AmigaBASIC
#include <jambo.h>

Main
   Set break
   a=1.5, b=1.5, r=0, origen x=200, origen y=105
   total = 0, Let ( total := Mul(20, M_PI) )
   Cls
   Loop for ( t=0, var 't' Is less equal to 'total', Let (t := Add (t, 0.005)) )
       #( r = a + b * t )
       Set 'origen x, origen y', # ( 200 + (2*r*sin(t)) ) » 'origen x', #( 105 + (r*cos(t)) ) » 'origen y', 
       Gosub 'Dibuja un segmento'
   Next
   Pause
End

Subrutines

Define (Dibuja un segmento, x1, y1, x2, y2)
  dx=0, dy=0, paso=0, i=0, DX=0, DY=0

  Sub(x2, x1), Sub (y2, y1), Move to ' dx, dy '

  Let( paso := Get if( Greater equal ( Abs(dx) » (DX), Abs(dy)»(DY) ), DX, DY ) )

  // incremento:
  Div(dx, paso), Div(dy, paso), Move to ( dx, dy )

  Color back (13)
  // dibuja línea:
  i = 0
  Loop if ( Less equal (i, paso) )
     Locate( y1, x1 ), Printnl( " " )
     Add ( x1, dx), Add( y1, dy ), Move to ( x1, y1 )
     ++i
  Back
  Printnl("\OFF")
Return
Output:
Invocar como:
    
    rxvt -g 500x250 -fn "xft:FantasqueSansMono-Regular:pixelsize=1" -e hopper jm/archi.jambo

APL

Works in: Dyalog APL

Uses Dyalog's SharpPlot integration, which works on all supported platforms.

  'InitCauseway' 'View' ⎕CY 'sharpplot'
  InitCauseway    ⍝ initialise current namespace
  sp⎕NEW Causeway.SharpPlot                                               
  sp.DrawPolarChart {(360|)}⌽⍳720
      View sp

See the plot on imgur.

AutoHotkey

Requires GDIP

if !pToken := Gdip_Startup()
{
	MsgBox, 48, gdiplus error!, Gdiplus failed to start. Please ensure you have gdiplus on your system
	ExitApp
}
OnExit, Exit
SysGet, MonitorPrimary, MonitorPrimary
SysGet, WA, MonitorWorkArea, %MonitorPrimary%
WAWidth	:= WARight-WALeft
WAHeight := WABottom-WATop
Gui, 1: -Caption +E0x80000 +LastFound +AlwaysOnTop +ToolWindow +OwnDialogs
Gui, 1: Show, NA
hwnd1 := WinExist()
hbm := CreateDIBSection(WAWidth, WAHeight)
hdc := CreateCompatibleDC()
obm := SelectObject(hdc, hbm)
G := Gdip_GraphicsFromHDC(hdc)
Gdip_SetSmoothingMode(G, 4)
pPen := Gdip_CreatePen(0xffff0000, 3)
;--------------------------------
a := 1, b := 4, th := 0.1, step := 0.1
loop, 720
{
	th += step
	r := a + b * th
	x1 := r * Cos(th)
	y1 := r * Sin(th)
	x1 += A_ScreenWidth/2
	y1 += A_ScreenHeight/2	
	if (x2 && y2)
		Gdip_DrawLine(G, pPen, x1, y1, x2, y2)
	x2 := x1, 	y2 := y1
	if GetKeyState("Esc", "P")
		break
	; next two lines are optional to watch it draw
	; Sleep 10
	; UpdateLayeredWindow(hwnd1, hdc, WALeft, WATop, WAWidth, WAHeight)
}
UpdateLayeredWindow(hwnd1, hdc, WALeft, WATop, WAWidth, WAHeight)
;--------------------------------
return

Exit:
Gdip_DeletePen(pPen)
SelectObject(hdc, obm)
DeleteObject(hbm)
DeleteDC(hdc)
Gdip_DeleteGraphics(G)
Gdip_Shutdown(pToken)
ExitApp
Return

AWK

# syntax: GAWK -f ARCHIMEDEAN_SPIRAL.AWK
# converted from Applesoft BASIC
BEGIN {
    x_min = y_min = 9999
    x_max = y_max = 0
    h = 96
    w = h + h / 2
    a = 1
    b = 1
    m = 6 * 3.1415926
    step = .02
    for (t=step; t<=m; t+=step) { # build spiral
      r = a + b * t
      x = int(r * cos(t) + w)
      y = int(r * sin(t) + h)
      if (x <= 0 || y <= 0) { continue }
      if (x >= 280 ) { continue }
      if (y >= 192) { continue }
      arr[x,y] = "*"
      x_min = min(x_min,x)
      x_max = max(x_max,x)
      y_min = min(y_min,y)
      y_max = max(y_max,y)
    }
    for (i=x_min; i<=x_max; i++) { # print spiral
      rec = ""
      for (j=y_min; j<=y_max; j++) {
        rec = sprintf("%s%1s",rec,arr[i,j])
      }
      printf("%s\n",rec)
    }
    exit(0)
}
function max(x,y) { return((x > y) ? x : y) }
function min(x,y) { return((x < y) ? x : y) }
Output:
             **********
          ***          ***
         **              **
       **                  **
      **                    **
     **                      **
    **         *******        **
   **       ***      ***       *
   *       **          **      **
  **      **            **      *
  *      **              **     **
 **     **                *      *
 *      *       ****       *     *
 *     *      ***  **      *     **
**     *      *     **     *      *
*      *     **      *     *      *
*      *     *       *     *      *
*     **     *      **     *      *
*     **     *     **      *     **
*      *     *            **     *
*      *     *            *      *
**     *      *          **     **
 *     *      **        **      *
 *      *      ***    ***      **
 **     **       ******        *
  *      *                    **
  *      **                  **
   *       **               **
   **       **            **
    *        ****       ***
     *          ********
      *
       *
        **
         ***
           ****
              *****

BASIC

AmigaBASIC

Translation of: Locomotive Basic
a=1.5
b=1.5 
pi=3.141592

PSET (320,100)
FOR t=0 TO 40*pi STEP .1
  r=a+b*t  
  LINE -(320+2*r*SIN(t),100+r*COS(t))
NEXT

Applesoft BASIC

110 LET H = 96
120 LET W = H + H / 2
130 HGR2 
140 HCOLOR= 3
150 LET A = 1
160 LET B = 9
170 LET PI = 3.1415926535
180 LET M = 10 * PI
190 LET S = .02
200 FOR T = S TO M STEP S
210     LET R = A + B * T
220     LET X = R *  COS (T) + W
230     LET Y = R *  SIN (T) + H
240     IF X < 0 THEN  290
250     IF Y < 0 THEN  290 
260     IF X > 279 THEN  290  
270     IF Y > 191 THEN  290
280     HPLOT X,Y
290 NEXT

BASIC256

# Basic-256 ver 1.1.4
# Archimedean Spiral

width = 430 : height = 430
graphsize width, height
rect 0,0, graphwidth,graphheight
penwidth 1
color green

x = width/2 : y = height/2            # Center of graphics window
i = 1 : t = 0 : xn = 0 : yn = 0       # Initial values
iter = 150 : q = 30

line x,0,x,height
line 0,y,width,y 

penwidth 2
color red

while i <= iter
    t = i / q * pi
    xn = (1 + (1 * t)) * cos(t) +x
    yn = (1 + (1 * t)) * sin(t) +y
    line x,y,xn,yn
    x = xn : y = yn    
    print i + chr(9) + int(x) + chr(9) + int(y) + chr(9) + int(t)    # chr(9) = TAB
    i += 1
end while

imgsave "spiral-Basic-256.png", "PNG"

BBC BASIC

File:Archimedean spiral bbc basic.jpeg
      A=320
      VDU 23, 22, A+10; A+10; 8, 16, 16, 128
      ORIGIN @size.x%, @size.y%
      GCOL 7
      FOR I=-(A - A MOD 100) TO A - A MOD 100 STEP 100
        LINE I, -A, I, A : LINE -A, I, A, I
      NEXT

      MOVE 0, 0
      GCOL 1
      VDU 23, 23, 3|
      FOR I=0 TO 5 * PI STEP .05
        R=A / 16 * I
        DRAW R * COS(I), R * SIN(I)
      NEXT

Chipmunk Basic

Works with: Chipmunk Basic version 3.6.4
10 rem Archimedean spiral
20 graphics 0
30 graphics cls
40 a = 3 : b = 1.4
50 x0 = 320 : y0 = 200
60 graphics moveto x0,y0
70 for t = 0 to 40*pi step 0.2
80 r = a+b*t
90 x = r*cos(t)+320 : y = r*sin(t)+200
100 graphics lineto x,y
110 next t
120 end

Commodore BASIC

Commodore BASIC 2.0 lacks in-built graphics capability. This implementation is written for Commodore BASIC 7.0 that was built into the Commodore 128 computer. Should also work for Commodore BASIC 3.5.

1 REM       ARCHIMEDEAN SPIRAL
2 REM   USING COMMODORE BASIC 7.0
3 REM      OF THE COMMODORE 128
4 REM **********************************
10 GRAPHIC 1,1
20 A = 1.5
30 B = 0.7
40 X0 = 160 : Y0 = 100
50 FOR T = 0 TO 40*π STEP 0.2
60 R = A+B*T
70 X = R*COS(T)+160 : Y = R*SIN(T)+100
80 DRAW 1,X0,Y0 TO X,Y
90 X0 = X : Y0 = Y
100 NEXT T
110 GOTO 110

FreeBASIC

' version 16-10-2016
' compile with: fbc -s gui

Const As double      deg2rad = Atn(1) * 4 / 180    ' pi = atn(1) * 4, pi/180

Const As UInteger screensize = 600                 ' size of window in pixels     
Const As Double        turns = 5                   ' number of turns
Const As UInteger   halfscrn = screensize \ 2    
Const As uinteger         sf = (turns * (screensize - 100)) / halfscrn 

ScreenRes screensize, screensize, 32   ' screen 600 * 600 pixels, 4 byte color

Dim As Double r, x, y 

For r = 0 To turns * 360 Step 0.05
  x = Cos(r * deg2rad) * r / sf 
  y = Sin(r * deg2rad) * r / sf
  PSet(halfscrn + x, halfscrn - y), RGB(255, 255, 255)  
Next

' empty keyboard buffer 
While InKey <> "" : Wend
Print : Print "hit any key to end program"
Sleep
End

GW-BASIC

10 A = 0
20 B = 1
30 SCREEN 1
40 FOR THETA = 0 TO 160 STEP .01
50 R = A + B*THETA
60 X = R*COS(THETA)
70 Y = R*SIN(THETA)
80 PSET (160+X, 100-Y),3
90 NEXT THETA
100 IF INKEY$="" THEN GOTO 100
110 SCREEN 2:SCREEN 0
120 END

IS-BASIC

100 GRAPHICS LORES 2
110 OPTION ANGLE DEGREES
120 PLOT 640,360,ANGLE 90;
130 FOR I=2 TO 33.2 STEP .05
140   PLOT FORWARD I,LEFT 5;
150 NEXT

Locomotive Basic

Translation of: Commodore BASIC
10 a=1.5:b=2
20 mode 2:rad:move 320,200
30 for t=0 to 40*pi step 0.2
40 r=a+b*t
50 draw r*sin(t)+320,r*cos(t)+200
60 next
70 while inkey$="":wend

PureBasic

#MAXLOOP  = 7*360
#XCENTER  = 640/2
#YCENTER  = 480/2
#SCALAR   = 200

If OpenWindow(0, 100, 200, 640, 480, "Archimedean spiral")  
  If CreateImage(0, 640, 480,24,RGB(255,255,255))
    If StartDrawing(ImageOutput(0))      
      i.f=0.0
      While i<=#MAXLOOP         
        x.f=#XCENTER+Cos(Radian(i))*#SCALAR*i/#MAXLOOP
        y.f=#YCENTER+Sin(Radian(i))*#SCALAR*i/#MAXLOOP
        Plot(x,y,RGB(50,50,50))
        i+0.05
      Wend
      StopDrawing()
    EndIf
  EndIf  
  ImageGadget(0, 0, 0, 0, 0, ImageID(0))        
  Repeat : Event = WaitWindowEvent() : Until Event = #PB_Event_CloseWindow 
EndIf
End

Run BASIC

    'archimedean spiral.bas
    'runs in Run Basic
    'Run Basic website http://www.runbasic.com
    'From Rosettacode.org/wiki/ *** Liberty_BASIC

  graphic #g, 300,300 'width and height - the center is 150
  c = 255  '255 for white '0 for black
  print "Welcome to the Arch-Spiral Program"

  pi=acs(-1)
  nLoops = 5
   #g cls("blue") 'blue background color
   #g color(c,c,c) 'set line color - see color above

  for t=0 to 2*pi*nLoops step 0.01
     'c = c - 1  'changes color parameter
     x=100*t/(2*pi*nLoops)*cos(t)+150  '150x150 is the center
     y=100*t/(2*pi*nLoops)*sin(t)+150 
     #g color(c,c,c)  'changes color
     #g set(x,y)
     'if c <1 then c=255
  next
    render #g

  print "Thank you and Goodbye"
  end
End

QBasic

SCREEN 12
WINDOW (-2.67, -2!)-(2.67, 2!)
PI = 4 * ATN(1)
H = PI / 40
A = .2: B = .05
PSET (A, 0)
FOR I = 0 TO 400
    T = I * H
    X = (A + B * T) * COS(T)
    Y = (A + B * T) * SIN(T)
    LINE -(X, Y)
NEXT

Sinclair ZX81 BASIC

Translation of: Applesoft BASIC

Works with the unexpanded (1k RAM) ZX81. The output is quite blocky, but identifiably a spiral.

10 LET A=1.5
20 LET B=0.7
30 FOR T=0 TO 7*PI STEP 0.05
40 LET R=A+B*T
50 PLOT R*COS T+32,R*SIN T+22
60 NEXT T
Output:

Screenshot here.

VBA

Private Sub plot_coordinate_pairs(x As Variant, y As Variant)
    Dim chrt As Chart
    Set chrt = ActiveSheet.Shapes.AddChart.Chart
    With chrt
        .ChartType = xlXYScatter
        .HasLegend = False
        .SeriesCollection.NewSeries
        .SeriesCollection.Item(1).XValues = x
        .SeriesCollection.Item(1).Values = y
    End With
End Sub
Public Sub main()
    Dim x(1000) As Single, y(1000) As Single
    a = 1
    b = 9
    For i = 0 To 1000
        theta = i * WorksheetFunction.Pi() / 60
        r = a + b * theta
        x(i) = r * Cos(theta)
        y(i) = r * Sin(theta)
    Next i
    plot_coordinate_pairs x, y
End Sub

Yabasic

Translation of: Sinclair_ZX81_BASIC
5 OPEN WINDOW 320, 200 : WINDOW ORIGIN "CC"
10 LET A=1.5
20 LET B=0.7
30 FOR T=0 TO 30*PI STEP 0.05
40 LET R=A+B*T
50 LINE TO R*COS(T),R*SIN(T)
60 NEXT T

BQN

The BQN online REPL supports some basic plotting functionality through •Plot. This is used to create a spiral plotting function:

{(•math.Sin •Plot(⊢×↕) •math.Cos) -(2×π) × 𝕩(↕÷-1)100}

When called with argument 200, it is similar to the given example diagram.

Try it out!

C

Interactive code which asks the parameters a and b as inputs, the number of cycles and the division steps. Requires the WinBGIm library.

#include<graphics.h>
#include<stdio.h>
#include<math.h>

#define pi M_PI

int main(){
	double a,b,cycles,incr,i;
	
	int steps,x=500,y=500;
	
	printf("Enter the parameters a and b : ");
	scanf("%lf%lf",&a,&b);
	
	printf("Enter cycles : ");
	scanf("%lf",&cycles);
	
	printf("Enter divisional steps : ");
	scanf("%d",&steps);
	
	incr = 1.0/steps;
	
	initwindow(1000,1000,"Archimedean Spiral");
	
	for(i=0;i<=cycles*pi;i+=incr){
		putpixel(x + (a + b*i)*cos(i),x + (a + b*i)*sin(i),15);
	}
	
	getch();
	
	closegraph();	
}

C#

using System;
using System.Linq;
using System.Drawing;
using System.Diagnostics;
using System.Drawing.Drawing2D;

class Program
{
    const int width = 380;
    const int height = 380;
    static PointF archimedeanPoint(int degrees)
    {
        const double a = 1;
        const double b = 9;
        double t = degrees * Math.PI / 180;
        double r = a + b * t;
        return new PointF { X = (float)(width / 2 + r * Math.Cos(t)), Y = (float)(height / 2 + r * Math.Sin(t)) };
    }

    static void Main(string[] args)
    {
        var bm = new Bitmap(width, height);
        var g = Graphics.FromImage(bm);
        g.SmoothingMode = SmoothingMode.AntiAlias;
        g.FillRectangle(new SolidBrush(Color.White), new Rectangle { X = 0, Y = 0, Width = width, Height = height });
        var pen = new Pen(Color.OrangeRed, 1.5f);

        var spiral = Enumerable.Range(0, 360 * 3).AsParallel().AsOrdered().Select(archimedeanPoint);
        var p0 = new PointF(width / 2, height / 2);
        foreach (var p1 in spiral)
        {
            g.DrawLine(pen, p0, p1);
            p0 = p1;
        }
        g.Save(); // is this really necessary ?
        bm.Save("archimedes-csharp.png");
        Process.Start("archimedes-csharp.png"); // Launches default photo viewing app
    }
}

C++

#include <windows.h>
#include <string>
#include <iostream>
 
const int BMP_SIZE = 600;
 
class myBitmap {
public:
    myBitmap() : pen( NULL ), brush( NULL ), clr( 0 ), wid( 1 ) {}
    ~myBitmap() {
        DeleteObject( pen ); DeleteObject( brush );
        DeleteDC( hdc ); DeleteObject( bmp );
    }
    bool create( int w, int h ) {
        BITMAPINFO bi;
        ZeroMemory( &bi, sizeof( bi ) );
        bi.bmiHeader.biSize        = sizeof( bi.bmiHeader );
        bi.bmiHeader.biBitCount    = sizeof( DWORD ) * 8;
        bi.bmiHeader.biCompression = BI_RGB;
        bi.bmiHeader.biPlanes      = 1;
        bi.bmiHeader.biWidth       =  w;
        bi.bmiHeader.biHeight      = -h;
        HDC dc = GetDC( GetConsoleWindow() );
        bmp = CreateDIBSection( dc, &bi, DIB_RGB_COLORS, &pBits, NULL, 0 );
        if( !bmp ) return false;
        hdc = CreateCompatibleDC( dc );
        SelectObject( hdc, bmp );
        ReleaseDC( GetConsoleWindow(), dc );
        width = w; height = h;
        return true;
    }
    void clear( BYTE clr = 0 ) {
        memset( pBits, clr, width * height * sizeof( DWORD ) );
    }
    void setBrushColor( DWORD bClr ) {
        if( brush ) DeleteObject( brush );
        brush = CreateSolidBrush( bClr );
        SelectObject( hdc, brush );
    }
    void setPenColor( DWORD c ) {
        clr = c; createPen();
    }
    void setPenWidth( int w ) {
        wid = w; createPen();
    }
    void saveBitmap( std::string path ) {
        BITMAPFILEHEADER fileheader;
        BITMAPINFO       infoheader;
        BITMAP           bitmap;
        DWORD            wb;
        GetObject( bmp, sizeof( bitmap ), &bitmap );
        DWORD* dwpBits = new DWORD[bitmap.bmWidth * bitmap.bmHeight];
        ZeroMemory( dwpBits, bitmap.bmWidth * bitmap.bmHeight * sizeof( DWORD ) );
        ZeroMemory( &infoheader, sizeof( BITMAPINFO ) );
        ZeroMemory( &fileheader, sizeof( BITMAPFILEHEADER ) );
        infoheader.bmiHeader.biBitCount = sizeof( DWORD ) * 8;
        infoheader.bmiHeader.biCompression = BI_RGB;
        infoheader.bmiHeader.biPlanes = 1;
        infoheader.bmiHeader.biSize = sizeof( infoheader.bmiHeader );
        infoheader.bmiHeader.biHeight = bitmap.bmHeight;
        infoheader.bmiHeader.biWidth = bitmap.bmWidth;
        infoheader.bmiHeader.biSizeImage = bitmap.bmWidth * bitmap.bmHeight * sizeof( DWORD );
        fileheader.bfType    = 0x4D42;
        fileheader.bfOffBits = sizeof( infoheader.bmiHeader ) + sizeof( BITMAPFILEHEADER );
        fileheader.bfSize    = fileheader.bfOffBits + infoheader.bmiHeader.biSizeImage;
        GetDIBits( hdc, bmp, 0, height, ( LPVOID )dwpBits, &infoheader, DIB_RGB_COLORS );
        HANDLE file = CreateFile( path.c_str(), GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, 
                                  FILE_ATTRIBUTE_NORMAL, NULL );
        WriteFile( file, &fileheader, sizeof( BITMAPFILEHEADER ), &wb, NULL );
        WriteFile( file, &infoheader.bmiHeader, sizeof( infoheader.bmiHeader ), &wb, NULL );
        WriteFile( file, dwpBits, bitmap.bmWidth * bitmap.bmHeight * 4, &wb, NULL );
        CloseHandle( file );
        delete [] dwpBits;
    }
    HDC getDC() const     { return hdc; }
    int getWidth() const  { return width; }
    int getHeight() const { return height; }
private:
    void createPen() {
        if( pen ) DeleteObject( pen );
        pen = CreatePen( PS_SOLID, wid, clr );
        SelectObject( hdc, pen );
    }
    HBITMAP bmp; HDC    hdc;
    HPEN    pen; HBRUSH brush;
    void    *pBits; int    width, height, wid;
    DWORD    clr;
};
class spiral {
public:
    spiral() {
        bmp.create( BMP_SIZE, BMP_SIZE );
    }
    void draw( int c, int s ) {
        double a = .2, b = .3, r, x, y;
        int w = BMP_SIZE >> 1;
        HDC dc = bmp.getDC();
        for( double d = 0; d < c * 6.28318530718; d += .002 ) {
            r = a + b * d; x = r * cos( d ); y = r * sin( d );
            SetPixel( dc, ( int )( s * x + w ), ( int )( s * y + w ), 255 );
        }
        // saves the bitmap
        bmp.saveBitmap( "./spiral.bmp" );
    }
private:
    myBitmap bmp;
};
int main(int argc, char* argv[]) {
    spiral s; s.draw( 16, 8 ); return 0;
}

Clojure

Works with: Incanter
(use '(incanter core stats charts io))

(defn Arquimidean-function
  [a b theta]
  (+ a (* theta b)))

(defn transform-pl-xy [r theta]
  (let [x (* r (sin theta))
        y (* r (cos theta))]
    [x y]))

(defn arq-spiral [t] (transform-pl-xy (Arquimidean-function 0 7 t) t))

(view (parametric-plot arq-spiral 0 (* 10 Math/PI)))

Another version inspired by the Java below, showing how to interop with awt/swing to do simple graphics:

(let [panel (proxy [javax.swing.JPanel] []
              (paintComponent [g]
                (proxy-super paintComponent g)
                (.setStroke g (java.awt.BasicStroke. 2))
                (.setRenderingHint g java.awt.RenderingHints/KEY_ANTIALIASING
                                   java.awt.RenderingHints/VALUE_ANTIALIAS_ON)
                (let [[a b] [0 (/ 1 Math/PI)]
                      [w h] [(.getWidth this) (.getHeight this)]
                      [cx cy] [(/ w 2.0) (/ h 2.0)]
                      margin 16
                      [rotations point-n] [3 (quot (min w h) 2)]
                      [ring-n line-n] [6 12]
                      scale (/ (- (min w h) (* 2 margin)) (* 2.0 ring-n))]
                  ;; Grid
                  (.setColor g (java.awt.Color. 0xEEEEEE))
                  (doseq [i (range 1 (inc ring-n))]
                    (let [[posx posy] [(- cx (* i scale)) (- cy (* i scale))]]
                      (.drawOval g posx posy (* 2 i scale) (* 2 i scale))))
                  (dotimes [i line-n]
                    (let [theta (* 2 Math/PI (/ i (double line-n)))
                          [x y] [(+ cx (* scale ring-n (Math/cos theta)))
                                 (+ cy (* scale ring-n (Math/sin theta)))]]
                      (.drawLine g cx cy x y)))
                  ;; Spiral
                  (.setColor g (java.awt.Color. 0x202020))
                  (loop [i 0 [x y] [(+ cx (* a scale)) cy]]
                    (let [p (/ (inc i) (double point-n))
                          theta (* rotations 2 Math/PI p)
                          r (* scale (+ a (* b theta)))
                          [x1 y1] [(+ cx (* r (Math/cos theta)))
                                   (- cy (* r (Math/sin theta)))]]
                      (.drawLine g x y x1 y1)
                      (when (< i (dec point-n)) (recur (inc i) [x1 y1])))))))]
  (doto (javax.swing.JFrame.)
    (.add (doto panel
            (.setPreferredSize (java.awt.Dimension. 640 640))
            (.setBackground java.awt.Color/white))
          java.awt.BorderLayout/CENTER)
    (.pack)
    (.setVisible true)))

Common Lisp

Common Lisp doesn't provide native graphical output. Libraries or bitmapped output could be used instead, but for this solution, the output is accomplished with character printing.

(defun draw-coords-as-text (coords size fill-char)
  (let* ((min-x (apply #'min (mapcar #'car coords)))
         (min-y (apply #'min (mapcar #'cdr coords)))
         (max-x (apply #'max (mapcar #'car coords)))
         (max-y (apply #'max (mapcar #'cdr coords)))
         (real-size (max (+ (abs min-x) (abs max-x)) ; bounding square
                         (+ (abs min-y) (abs max-y))))
         (scale-factor (* (1- size) (/ 1 real-size)))
         (center-x (* scale-factor -1 min-x))
         (center-y (* scale-factor -1 min-y))
         (intermediate-result (make-array (list size size) 
                                          :element-type 'char 
                                          :initial-element #\space)))
    (dolist (c coords)
      (let ((final-x (floor (+ center-x (* scale-factor (car c)))))
            (final-y (floor (+ center-y (* scale-factor (cdr c))))))  
        (setf (aref intermediate-result final-x final-y)
              fill-char)))
    ; print results to output
    (loop for i below (array-total-size intermediate-result) do
          (when (zerop (mod i size))
            (terpri))
          (princ (row-major-aref intermediate-result i)))))


(defun spiral (a b step-resolution step-count)
  "Returns a list of coordinates for r=a+b*theta stepping theta by step-resolution"
  (loop for theta 
        from 0 upto (* step-count step-resolution)
        by step-resolution
        for r = (+ a (* b theta))
        for x = (* r (cos theta))
        for y = (* r (sin theta))
        collect (cons x y)))

(draw-coords-as-text (spiral 10 10 0.01 1500) 30 #\*)
; Output:
; 
;                         *     
;          ******          *    
;       ****    ***        **   
;     ***          **       *   
;    **             **       *  
;   **               **      *  
;   *                 **     ** 
;  **                  *      * 
; **       ******      *      * 
; *       **    **     **     * 
; *      **      *      *     * 
; *     **       *      *     **
; *     *        *      *     * 
; *     *     * **      *     * 
; *     *     ***      **     * 
; *     **             *      * 
; *      *            **      * 
; *      **          **      ** 
; **      **        **       *  
;  *       **      **       **  
;  **       ********        *   
;   *                      **   
;   **                    **    
;    **                  **     
;     **               ***      
;       **            **        
;        ****      ***          
;           *******             
;

Craft Basic

bgcolor 0, 0, 0
cls graphics
fgcolor 255, 255, 0

define pi = 3.14, size = 80
define x = 250, y = 200
define a = 1.5, b = .7

for t = 0 to size * pi step .1

	let r = a + b * t
	dot r * cos(t) + x, r * sin(t) + y
	wait

next t

Delphi

Works with: Delphi version 6.0


procedure ArcSpiral(Image: TImage);
var Radius,Theta: double;
var X,Y: integer;
var Center: TPoint;
const Step = 0.2;
const Offset = 3; Spacing = 1.4;
begin
Image.Canvas.Brush.Color:=clWhite;
Image.Canvas.Rectangle(0,0,Image.Width,Image.Height);
Center:=Point(Image.Width div 2, Image.Height div 2);
Image.Canvas.MoveTo(Center.X,Center.Y);
Theta:=0;
while Theta<(40*Pi) do
	begin
	{Radius increases as theta increases}
	Radius:=Offset+Spacing*Theta;
	{Calculate position on circle}
	X:=Trunc(Radius*Cos(Theta)+Center.X);
	Y:=Trunc(Radius*sin(Theta)+Center.Y);
	Image.Canvas.LineTo(X,Y);
	Theta:=Theta+Step;
	end;
end;
Output:

EasyLang

Run it

linewidth 0.4
x = 50
y = 50
while r < 50
   line r * cos t + x r * sin t + y
   r += 0.05
   t += 3
.

FOCAL

1.1 S A=1.5
1.2 S B=2
1.3 S N=250
1.4 F T=1,N; D 2
1.5 X FSKP(2*N)
1.6 Q

2.1 S R=A+B*T; D 3
2.2 X FPT(2*T,X1+512,Y1+390)
2.3 S R=A+B*(T+1); D 4
2.4 X FVEC(2*T+1,X2-X1,Y2-Y1)

3.1 S X1=R*FSIN(.2*T)
3.2 S Y1=R*FCOS(.2*T)

4.1 S X2=R*FSIN(.2*(T+1))
4.2 S Y2=R*FCOS(.2*(T+1))

This program uses FOCAL-11 on a DEC GT40 vector graphics terminal.

Frege

Translation of: Java
Works with: Frege version 3.23.888
module Archimedean where

import Java.IO
import Prelude.Math

data BufferedImage = native java.awt.image.BufferedImage where
  pure native type_3byte_bgr "java.awt.image.BufferedImage.TYPE_3BYTE_BGR" :: Int
  native new :: Int -> Int -> Int -> STMutable s BufferedImage
  native createGraphics :: Mutable s BufferedImage -> STMutable s Graphics2D

data Color = pure native java.awt.Color where
  pure native orange "java.awt.Color.orange" :: Color
  pure native white "java.awt.Color.white" :: Color
  pure native new :: Int -> Color

data BasicStroke = pure native java.awt.BasicStroke where
  pure native new :: Float -> BasicStroke

data RenderingHints = native java.awt.RenderingHints where
  pure native key_antialiasing "java.awt.RenderingHints.KEY_ANTIALIASING" :: RenderingHints_Key
  pure native value_antialias_on "java.awt.RenderingHints.VALUE_ANTIALIAS_ON" :: Object

data RenderingHints_Key = pure native java.awt.RenderingHints.Key

data Graphics2D = native java.awt.Graphics2D where
  native drawLine :: Mutable s Graphics2D -> Int -> Int -> Int -> Int -> ST s ()
  native drawOval :: Mutable s Graphics2D -> Int -> Int -> Int -> Int -> ST s ()
  native fillRect :: Mutable s Graphics2D -> Int -> Int -> Int -> Int -> ST s ()
  native setColor :: Mutable s Graphics2D -> Color -> ST s ()
  native setRenderingHint :: Mutable s Graphics2D -> RenderingHints_Key -> Object -> ST s ()
  native setStroke :: Mutable s Graphics2D -> BasicStroke -> ST s ()

data ImageIO = mutable native javax.imageio.ImageIO where
  native write "javax.imageio.ImageIO.write" :: MutableIO BufferedImage -> String -> MutableIO File -> IO Bool throws IOException

width = 640
center = width `div` 2

roundi = fromIntegral . round

drawGrid :: Mutable s Graphics2D -> ST s ()
drawGrid g = do
  g.setColor $ Color.new 0xEEEEEE
  g.setStroke $ BasicStroke.new 2
  let angle = toRadians 45
      margin = 10
      numRings = 8
      spacing = (width - 2 * margin) `div` (numRings * 2)
  forM_ [0 .. numRings-1] $ \i -> do
    let pos = margin + i * spacing
        size = width - (2 * margin + i * 2 * spacing)
        ia = fromIntegral i * angle
        multiplier = fromIntegral $ (width - 2 * margin) `div` 2
        x2 = center + (roundi (cos ia * multiplier))
        y2 = center - (roundi (sin ia * multiplier))
    g.drawOval pos pos size size
    g.drawLine center center x2 y2

drawSpiral :: Mutable s Graphics2D -> ST s ()
drawSpiral g = do
  g.setStroke $ BasicStroke.new 2
  g.setColor $ Color.orange
  let degrees = toRadians 0.1
      end = 360 * 2 * 10 * degrees
      a = 0
      b = 20
      c = 1
      drSp theta = do
        let r = a + b * theta ** (1 / c)
            x = r * cos theta
            y = r * sin theta
            theta' = theta + degrees
        plot g (center + roundi x) (center - roundi y)
        when (theta' < end) (drSp (theta' + degrees))
  drSp 0

plot :: Mutable s Graphics2D -> Int -> Int -> ST s ()
plot g x y = g.drawOval x y 1 1

main = do
  buffy <- BufferedImage.new width width BufferedImage.type_3byte_bgr
  g <- buffy.createGraphics
  g.setRenderingHint RenderingHints.key_antialiasing RenderingHints.value_antialias_on
  g.setColor Color.white
  g.fillRect 0 0 width width
  drawGrid g
  drawSpiral g
  f <- File.new "SpiralFrege.png"
  void $ ImageIO.write buffy "png" f

Output is here due to Is file uploading blocked forever?

Frink

p = new polyline
g = new graphics
a = 1
b = 1
for theta = 0 to 10 circle step 1 degree
{
   r = a + b theta
   x = r cos[theta]
   y = r sin[theta]
   p.addPoint[x,-y]
}

g.add[p]
g.show[]
g.write["ArchimedeanSpiralFrink.svg",800,800]

FutureBasic

_maxPoints = 190

void local fn DoIt
  window 1, @"Archimedean Spiral", (0,0,500,500)
  WindowSetBackgroundColor( 1, fn ColorBlack )
  pen 3, fn ColorRed
  
  float x, y, angle
  long i, a = 10, b = 10, x1 = 250, y1 = 250
  for i = 0 to _maxPoints - 1
    angle = 0.1 * i
    x = (a + b * angle) * cos(angle) + 250
    y = (a + b * angle) * sin(angle) + 250
    line x1,y1 to x,y
    x1 = x : y1 = y
  next
end fn

fn DoIt

HandleEvents
Output:

Go

Works with: go version 1.9

Creates a PNG file using only built-in packages.

package main

import (
	"image"
	"image/color"
	"image/draw"
	"image/png"
	"log"
	"math"
	"os"
)

func main() {
	const (
		width, height = 600, 600
		centre        = width / 2.0
		degreesIncr   = 0.1 * math.Pi / 180
		turns         = 2
		stop          = 360 * turns * 10 * degreesIncr
		fileName      = "spiral.png"
	)

	img := image.NewNRGBA(image.Rect(0, 0, width, height)) // create new image
	bg := image.NewUniform(color.RGBA{255, 255, 255, 255}) // prepare white for background
	draw.Draw(img, img.Bounds(), bg, image.ZP, draw.Src)   // fill the background
	fgCol := color.RGBA{255, 0, 0, 255}                    // red plot

	a := 1.0
	b := 20.0

	for theta := 0.0; theta < stop; theta += degreesIncr {
		r := a + b*theta
		x := r * math.Cos(theta)
		y := r * math.Sin(theta)
		img.Set(int(centre+x), int(centre-y), fgCol)
	}

	imgFile, err := os.Create(fileName)
	if err != nil {
		log.Fatal(err)
	}
	defer imgFile.Close()

	if err := png.Encode(imgFile, img); err != nil {
		imgFile.Close()
		log.Fatal(err)
	}
}

Haskell

Works with: GHC version 7.8.3
Works with: GHC version 8.0.1
Library: Juicy.Pixels
Library: Rasterific
#!/usr/bin/env stack
-- stack --resolver lts-7.0 --install-ghc runghc --package Rasterific --package JuicyPixels

import Codec.Picture( PixelRGBA8( .. ), writePng )
import Graphics.Rasterific
import Graphics.Rasterific.Texture
import Graphics.Rasterific.Transformations

archimedeanPoint a b t = V2 x y
  where r = a + b * t
        x = r * cos t
        y = r * sin t

main :: IO ()
main = do
  let white = PixelRGBA8 255 255 255 255
      drawColor = PixelRGBA8 0xFF 0x53 0x73 255
      size = 800
      points = map (archimedeanPoint 0 10) [0, 0.01 .. 60]
      hSize = fromIntegral size / 2
      img = renderDrawing size size white $
            withTransformation (translate $ V2 hSize hSize) $
            withTexture (uniformTexture drawColor) $
            stroke 4 JoinRound (CapRound, CapRound) $
            polyline points

  writePng "SpiralHaskell.png" img

Output is here due to Is file uploading blocked forever?

J

require'plot'
'aspect 1' plot (*^)j.0.01*i.1400

Java

Works with: Java version 8
import java.awt.*;
import static java.lang.Math.*;
import javax.swing.*;

public class ArchimedeanSpiral extends JPanel {

    public ArchimedeanSpiral() {
        setPreferredSize(new Dimension(640, 640));
        setBackground(Color.white);
    }

    void drawGrid(Graphics2D g) {
        g.setColor(new Color(0xEEEEEE));
        g.setStroke(new BasicStroke(2));

        double angle = toRadians(45);

        int w = getWidth();
        int center = w / 2;
        int margin = 10;
        int numRings = 8;

        int spacing = (w - 2 * margin) / (numRings * 2);

        for (int i = 0; i < numRings; i++) {
            int pos = margin + i * spacing;
            int size = w - (2 * margin + i * 2 * spacing);
            g.drawOval(pos, pos, size, size);

            double ia = i * angle;
            int x2 = center + (int) (cos(ia) * (w - 2 * margin) / 2);
            int y2 = center - (int) (sin(ia) * (w - 2 * margin) / 2);

            g.drawLine(center, center, x2, y2);
        }
    }

    void drawSpiral(Graphics2D g) {
        g.setStroke(new BasicStroke(2));
        g.setColor(Color.orange);

        double degrees = toRadians(0.1);
        double center = getWidth() / 2;
        double end = 360 * 2 * 10 * degrees;
        double a = 0;
        double b = 20;
        double c = 1;

        for (double theta = 0; theta < end; theta += degrees) {
            double r = a + b * pow(theta, 1 / c);
            double x = r * cos(theta);
            double y = r * sin(theta);
            plot(g, (int) (center + x), (int) (center - y));
        }
    }

    void plot(Graphics2D g, int x, int y) {
        g.drawOval(x, y, 1, 1);
    }

    @Override
    public void paintComponent(Graphics gg) {
        super.paintComponent(gg);
        Graphics2D g = (Graphics2D) gg;
        g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                RenderingHints.VALUE_ANTIALIAS_ON);

        drawGrid(g);
        drawSpiral(g);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> {
            JFrame f = new JFrame();
            f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            f.setTitle("Archimedean Spiral");
            f.setResizable(false);
            f.add(new ArchimedeanSpiral(), BorderLayout.CENTER);
            f.pack();
            f.setLocationRelativeTo(null);
            f.setVisible(true);
        });
    }
}

JavaScript

ES5

Works with: Chrome
File:ASjs.png
Output ASjs.png
<!-- ArchiSpiral.html -->
<html>
<head><title>Archimedean spiral</title></head>
<body onload="pAS(35,'navy');">
<h3>Archimedean spiral</h3> <p id=bo></p>
<canvas id="canvId" width="640" height="640" style="border: 2px outset;"></canvas>
<script>
// Plotting Archimedean_spiral aev 3/17/17
// lps - number of loops, clr - color.
function pAS(lps,clr) {
  var a=.0,ai=.1,r=.0,ri=.1,as=lps*2*Math.PI,n=as/ai;
  var cvs=document.getElementById("canvId");
  var ctx=cvs.getContext("2d");
  ctx.fillStyle="white"; ctx.fillRect(0,0,cvs.width,cvs.height);
  var x=y=0, s=cvs.width/2;
  ctx.beginPath();
  for (var i=1; i<n; i++) {
    x=r*Math.cos(a), y=r*Math.sin(a);
    ctx.lineTo(x+s,y+s);
    r+=ri; a+=ai;
  }//fend i
  ctx.strokeStyle = clr; ctx.stroke();
}
</script></body></html>
Output:
Page with Archimedean spiral like ASjs.png. Right-clicking on the canvas you can save 
spiral as a png-file, for example. 

ES6

Assumes the same HTML canvas embedding as above, but is functionally composed. Defines and logs a set of points, before rendering them to canvas.

<html>
<head>
    <title>Archimedean spiral</title>
    <style>h3 {font-family:sans-serif; color:gray;}</style>
</head>
<body onload="main('red')(15)">
<h3>Archimedean spiral</h3></p>
<canvas id="spiral" width="640" height="640" style="border: 2px outset;"></canvas>
<script>
const main = strColor => intCycles => {
    const
        ai = 0.05,
        ri = 0.1,
        cvs = document.getElementById('spiral'),
        ctx = cvs.getContext('2d'),
        s = cvs.width / 2,

        points = enumFromTo(1)(
            Math.PI * 2 * intCycles / ai
        ).map(i => [Math.cos, Math.sin].map(
            f => ri * i * f(ai * i) + s
        ));

    return (
        console.log(points),
        ctx.fillStyle = 'white',
        ctx.fillRect(0, 0, cvs.width, cvs.height),
        ctx.beginPath(),

        points.forEach(xy => ctx.lineTo(...xy)),

        ctx.strokeStyle = strColor,
        ctx.stroke(),
        points
    );
};

// enumFromTo :: Int -> Int -> [Int]
const enumFromTo = m => n =>
    Array.from({
        length: 1 + n - m
    }, (_, i) => m + i);
</script></body></html>

jq

Works with: jq

Works with gojq, the Go implementation of jq

SVG version

def spiral($zero; $turns; $step):

  def pi: 1 | atan * 4;
  def p2: (. * 100 | round) / 100;

  def svg:
    400 as $width
    | 400 as $height
    | 2 as $swidth # stroke
    | "blue" as $stroke
    | (range($zero; $turns * 2 * pi; $step) as $theta
       | (((($theta)|cos) * 2 * $theta + ($width/2)) |p2) as $x
       | (((($theta)|sin) * 2 * $theta + ($height/2))|p2) as $y
       | if $theta == $zero
         then "<path fill='transparent' style='stroke:\($stroke); stroke-width:\($swidth)' d='M \($x) \($y)"
         else " L \($x) \($y)"
         end),
      "' />";

  "<svg width='100%' height='100%' 
        xmlns='http://www.w3.org/2000/svg'>",
        svg,
  "</svg>" ;

spiral(0; 10; 0.025)
Output:

PNG version of SVG file (Please feel free to upload to RC)

ASCII Art Version

Translation of: awk
def spiral($a; $b; $step; $h):
  def min($x;$y): if $x <= $y then $x else $y end;
  def max($x;$y): if $x <= $y then $y else $x end;
  def pi: 1 | atan * 4;
  
  (6 * pi) as $m
  | ($h * 1.5) as $w
  | { x_min: 9999, y_min: 9999,
      x_max:    0, y_max:    0,
      arr: [] }
  | reduce range($step; $m+$step; $step) as $t (.;
      .r = $a + $b * $t
      | ((.r * ($t|cos) + $w) | round) as $x
      | ((.r * ($t|sin) + $h) | round) as $y
      | if   $x <= 0 or $y <= 0 then .
        elif $x >= 280          then .
        elif $y >= 192          then .
        else .arr[$x][$y] = "*"
        | .x_min = min(.x_min; $x)
        | .x_max = max(.x_max; $x)
        | .y_min = min(.y_min; $y)
        | .y_max = max(.y_max; $y)
	end )
  # ... and print it
  | .arr as $arr
  | range(.x_min; .x_max + 1) as $i
  | reduce range(.y_min; .y_max+1) as $j ( "";
      . + ($arr[$i][$j] // " ") )
  | "\(.)\n" ;

spiral(1; 1; 0.02; 96)
Output:

As for awk.

Julia

Works with: Julia version 0.6
using UnicodePlots

spiral(θ, a=0, b=1) = @. b * θ * cos(θ + a), b * θ * sin(θ + a)

x, y = spiral(1:0.1:10)
println(lineplot(x, y))
Output:
       ┌────────────────────────────────────────┐ 
    10 │⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡆⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣀⣀⠤⠤⠤⠤⠤⠤⡧⠤⣀⣀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⠀⠀⠀⠀⠀⠀⢀⡠⠔⠊⠉⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠉⠓⠤⢄⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⠀⠀⠀⠀⡠⠊⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠉⠢⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⠀⠀⡠⠊⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠘⢤⠀⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⠀⡜⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢇⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⡸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣀⠔⠊⠉⠉⠙⣧⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀│ 
       │⠤⡧⠤⠤⠤⠤⠤⠤⠤⠤⠤⠤⠤⡴⠥⠤⠤⠤⠤⠤⡧⠤⠤⠤⠤⠤⠤⠤⠤⠤⠤⠤⡼⠤⠤⠤⠤⠤⠤⠄│ 
       │⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢣⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣰⠁⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⢇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⢆⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⣀⠜⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⠘⡄⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠉⠒⠤⣀⡀⡇⠀⠀⠀⣀⣀⠤⠔⠊⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⠀⠘⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⡏⠉⠉⠉⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
       │⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
   -10 │⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀│ 
       └────────────────────────────────────────┘ 
       -10                                     10

Kotlin

Translation of: Java
// version 1.1.0

import java.awt.*
import javax.swing.*

class ArchimedeanSpiral : JPanel() {
    init {
        preferredSize = Dimension(640, 640)
        background = Color.white
    }

    private fun drawGrid(g: Graphics2D) {
        g.color = Color(0xEEEEEE)
        g.stroke = BasicStroke(2f)
        val angle = Math.toRadians(45.0)
        val w = width
        val center = w / 2
        val margin = 10
        val numRings = 8
        val spacing = (w - 2 * margin) / (numRings * 2)

        for (i in 0 until numRings) {
            val pos = margin + i * spacing
            val size = w - (2 * margin + i * 2 * spacing)
            g.drawOval(pos, pos, size, size)
            val ia = i * angle
            val x2 = center + (Math.cos(ia) * (w - 2 * margin) / 2).toInt()
            val y2 = center - (Math.sin(ia) * (w - 2 * margin) / 2).toInt()
            g.drawLine(center, center, x2, y2)
        }
    }

    private fun drawSpiral(g: Graphics2D) {
        g.stroke = BasicStroke(2f)
        g.color = Color.magenta
        val degrees = Math.toRadians(0.1)
        val center = width / 2
        val end = 360 * 2 * 10 * degrees
        val a = 0.0
        val b = 20.0
        val c = 1.0
        var theta = 0.0
        while (theta < end) {
            val r = a + b * Math.pow(theta, 1.0 / c)
            val x = r * Math.cos(theta)
            val y = r * Math.sin(theta)
            plot(g, (center + x).toInt(), (center - y).toInt())
            theta += degrees
        }
    }

    private fun plot(g: Graphics2D, x: Int, y: Int) {
        g.drawOval(x, y, 1, 1)
    }

    override fun paintComponent(gg: Graphics) {
        super.paintComponent(gg)
        val g = gg as Graphics2D
        g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON)
        drawGrid(g)
        drawSpiral(g)
    }
}

fun main(args: Array<String>) {
    SwingUtilities.invokeLater {
        val f = JFrame()
        f.defaultCloseOperation = JFrame.EXIT_ON_CLOSE
        f.title = "Archimedean Spiral"
        f.isResizable = false
        f.add(ArchimedeanSpiral(), BorderLayout.CENTER)
        f.pack()
        f.setLocationRelativeTo(null)
        f.isVisible = true
    }
}

Lambdatalk

1) from polar to cartesian coordinates

x = r*cos(t) = (a+b*t)*cos(t)
y = r*sin(t) = (a+b*t)*sin(t)

2) define the curve

{def CURVE       
 {lambda {:a :b :t}    
  {* {+ :a {* :b :t}} {cos :t}}     
  {* {+ :a {* :b :t}} {sin :t}}  
}}
-> CURVE

3) and draw it using SVG

{{SVG 580}
 {g {AXES 580 580}
  {polyline {@ points="{S.map {CURVE 5 4} 
                              {S.serie 0 {* 10 {PI}} 0.1}}"  
               {stroke red 3}}
}}}

The ouput can be seen in http://lambdaway.free.fr/lambdawalks/?view=archimedian_spiral


Lua

Library: LÖVE
Works with: LÖVE version 11.3
a=1
b=2
cycles=40
step=0.001
x=0
y=0

function love.load()
     x = love.graphics.getWidth()/2
     y = love.graphics.getHeight()/2
end

function love.draw()
     love.graphics.print("a="..a,16,16)
     love.graphics.print("b="..b,16,32)

     for i=0,cycles*math.pi,step do
          love.graphics.points(x+(a + b*i)*math.cos(i),y+(a + b*i)*math.sin(i))
     end
end

M2000 Interpreter

module Archimedean_spiral {
	smooth on ' enable GDI+
	def r(θ)=5+3*θ
	cls #002222,0
	pen #FFFF00
	refresh 5000
	every 1000 {
		\\ redifine window (console width and height) and place it to center (symbol ;)
		Window 12, random(10, 18)*1000, random(8, 12)*1000;
		move scale.x/2, scale.y/2
		let N=2, k1=pi/120, k=k1, op=5, op1=1
		for i=1 to int(1200*min.data(scale.x, scale.y)/18000)
			pen op
			swap op, op1
			Width 3 {draw angle k, r(k)*n}
			k+=k1
		next
		refresh 5000
		\\ press space to exit loop
		if  keypress(32) then exit
	}
	pen 14
	cls 5
	refresh 50
}
Archimedean_spiral

Maple

plots[polarplot](1+2*theta, theta = 0 .. 6*Pi)

Mathematica/Wolfram Language

The built-in function PolarPlot easily creates the desired plot

With[{a = 5, b = 4}, PolarPlot[a + b t, {t, 0, 10 Pi}]]

MATLAB

a = 1;
b = 1;
turns = 2;
theta = 0:0.1:2*turns*pi;
polarplot(theta, a + b*theta);

Maxima

Using draw package

archi_spi(a,b):=wxdraw2d(nticks=200,polar(a+b*theta,theta,1,10*%pi))$
archi_spi(1,1);
File:Archi spi.png

MiniScript

For use with the Mini Micro.

clear
x0 = gfx.width / 2
y0 = gfx.height / 2
gfx.clear color.white
for t in range(0, 70 * pi, 0.1)
	r = 3.2+ 1.5 * t
	x = r * cos(t) + gfx.width / 2
	y = r * sin(t) + gfx.height / 2
	gfx.line x0, y0, x, y, color.black,2
	x0 = x; y0 = y
end for

Alternative version using a Turtle library included with the Mini Micro.

import "turtle"
radToDegrees = function(rad)
	return 180 * rad / pi
end function

clear
print Turtle.displayNum
display(Turtle.displayNum).clear
t = new Turtle
for i in range(0, 50, 0.04)
	t.forward i 
	t.left radToDegrees(pi/20)
end for

Nim

Library: gintro
import math

import gintro/[glib, gobject, gtk, gio, cairo]

const

  Width = 601
  Height = 601

  Limit = 12 * math.PI

  Origin = (x: float(Width div 2), y: float(Height div 2))
  B = floor((Width div 2) / Limit)

#---------------------------------------------------------------------------------------------------

proc draw(area: DrawingArea; context: Context) =
  ## Draw the spiral.

  var theta = 0.0
  var delta = 0.01
  var (prevx, prevy) = Origin

  # Clear the region.
  context.moveTo(0, 0)
  context.setSource(0.0, 0.0, 0.0)
  context.paint()

  # Draw the spiral.
  context.setSource(1.0, 1.0, 0.0)
  context.moveTo(Origin.x, Origin.y)
  while theta < Limit:
    let r = B * theta
    let x = Origin.x + r * cos(theta)   # X-coordinate on drawing area.
    let y = Origin.y + r * sin(theta)   # Y-coordinate on drawing area.
    context.lineTo(x, y)
    context.stroke()
    # Set data for next round.
    context.moveTo(x, y)
    prevx = x
    prevy = y
    theta += delta

#---------------------------------------------------------------------------------------------------

proc onDraw(area: DrawingArea; context: Context; data: pointer): bool =
  ## Callback to draw/redraw the drawing area contents.

  area.draw(context)
  result = true

#---------------------------------------------------------------------------------------------------

proc activate(app: Application) =
  ## Activate the application.

  let window = app.newApplicationWindow()
  window.setSizeRequest(Width, Height)
  window.setTitle("Archimedean spiral")

  # Create the drawing area.
  let area = newDrawingArea()
  window.add(area)

  # Connect the "draw" event to the callback to draw the spiral.
  discard area.connect("draw", ondraw, pointer(nil))

  window.showAll()

#———————————————————————————————————————————————————————————————————————————————————————————————————

let app = newApplication(Application, "Rosetta.spiral")
discard app.connect("activate", activate)
discard app.run()

PARI/GP

Note: cartes2() can be found here on PARI/GP page.

Works with: PARI/GP version 2.7.4 and above
File:ArchiSpiral1.png
Output ArchiSpiral1.png
File:ArchiSpiral2.png
Output ArchiSpiral2.png
\\ The Archimedean spiral  
\\ ArchiSpiral() - Where: lps is a number of loops, c is a direction 0/1
\\ (counter-clockwise/clockwise). 6/6/16 aev
\\ Note: cartes2() can be found here on 
\\ http://rosettacode.org/wiki/Polyspiral#PARI.2FGP page.
ArchiSpiral(size,lps,c=0)={
my(a=.0,ai=.1,r=.0,ri=.1,as=lps*2*Pi,n=as/ai,x,y,vc,vx=List(.0),vy=vx);
if(c<0||c>1, c=0); if(c, ai*=-1);
print(" *** The Archimedean spiral: size=",size," loops=",lps," c=",c);
for(i=1, n, vc=cartes2(r,a); x=vc[1]; y=vc[2];
    listput(vx,x); listput(vy,y);
    r+=ri; a+=ai;
);\\fend i
plothraw(Vec(vx),Vec(vy));
}
{\\ Executing:
ArchiSpiral(640,5);   \\ArchiSpiral1.png
ArchiSpiral(640,5,1); \\ArchiSpiral2.png
}
Output:
> ArchiSpiral(640,5);  \\ArchiSpiral1.png
 *** The Archimedean spiral: size=640 loops=5 c=0
> ArchiSpiral(640,5,1);  \\ArchiSpiral2.png
 *** The Archimedean spiral: size=640 loops=5 c=1

Perl

Translation of: Raku
use Imager;
use constant PI => 3.14159265;

my ($w, $h) = (400, 400);
my $img = Imager->new(xsize => $w, ysize => $h);

for ($theta = 0; $theta < 52*PI; $theta += 0.025) {
    $x = $w/2 + $theta * cos($theta/PI);
    $y = $h/2 + $theta * sin($theta/PI);
    $img->setpixel(x => $x, y => $y, color => '#FF00FF');
}

$img->write(file => 'Archimedean-spiral.png');

Phix

Translation of: zkl
Library: Phix/pGUI
Library: Phix/online

You can run this online here.

--
-- demo\rosetta\Archimedean_spiral.exw
-- ===================================
--
with javascript_semantics
include pGUI.e

Ihandle dlg, canvas
cdCanvas cddbuffer, cdcanvas

function redraw_cb(Ihandle /*ih*/)
    integer {w, h} = IupGetIntInt(canvas, "DRAWSIZE"),
            a = 0, b = 5, cx = floor(w/2), cy = floor(h/2)
    cdCanvasActivate(cddbuffer)
    for deg=0 to 360*7 do
        atom rad = deg*PI/180,
             r = rad*b + a
        integer x = cx + floor(r*cos(rad)),
                y = cy + floor(r*sin(rad))
        cdCanvasPixel(cddbuffer, x, y, #00FF00) 
    end for
    cdCanvasFlush(cddbuffer)
    return IUP_DEFAULT
end function

function map_cb(Ihandle ih)
    cdcanvas = cdCreateCanvas(CD_IUP, ih)
    cddbuffer = cdCreateCanvas(CD_DBUFFER, cdcanvas)
    cdCanvasSetBackground(cddbuffer, CD_WHITE)
    cdCanvasSetForeground(cddbuffer, CD_RED)
    return IUP_DEFAULT
end function

procedure main()
    IupOpen()
    canvas = IupCanvas("RASTERSIZE=500x500") -- initial size
    IupSetCallbacks(canvas, {"MAP_CB", Icallback("map_cb"),
                             "ACTION", Icallback("redraw_cb")})
    dlg = IupDialog(canvas,`TITLE="Archimedean spiral"`)
    IupShow(dlg)
    IupSetAttribute(canvas, "RASTERSIZE", NULL) -- release the minimum limitation
    if platform()!=JS then
        IupMainLoop()
        IupClose()
    end if
end procedure

main()

Processing

Processing examples are animated, with a new point / segment added each draw() frame. Because Processing includes multiple built-in ways for drawing in rotating frames of reference, there are several ways to approach the Archimedean spiral problem.

Java mode

with points

When drawn with points the rotation must be very small, and initially the animation is very slow. This is because the points will move further and further apart as the radius increases.

float x, y;
float theta;
float rotation;

void setup() {
  size(300, 300);
  theta = 0;
  rotation = 0.1;
  background(255);
}

void draw() {
  translate(width/2.0, height/2.0);
  x = theta*cos(theta/PI); 
  y = theta*sin(theta/PI);
  point(x, y);   
  theta = theta + rotation;
  // check restart
  if (x>width/2.0) frameCount=-1;
}

with points, rotated

Rotates the canvas matrix using the built-in rotate() and draws a simple point, rather than computing rotated coordinates with sin()/cos().

float theta;
float rotation;

void setup() {
  size(300, 300);
  theta = 0;
  rotation = 0.1;
  background(255);
}

void draw() {
  translate(width/2.0, height/2.0);
  theta += rotation;
  rotate(theta/PI);
  point(theta, 0);
  // check restart
  if (theta>width/2.0) frameCount=-1;
}

with points, vector

Rotates a vector object of increasing magnitude using the built-in PVector and draws its point, rather than computing rotated coordinates with sin()/cos().

PVector pv;
float rotation;

void setup() {
  size(300, 300);
  rotation = 0.1;
  pv = new PVector(rotation, 0);
  background(255);
}

void draw() {
  translate(width/2.0, height/2.0);
  pv.setMag(pv.mag()+rotation);
  println(pv.mag());
  pv.rotate(rotation/PI);
  point(pv.x, pv.y);
  // check restart
  if (pv.mag()>width/2.0) frameCount=-1;
}

with line segments

Draw each new line segments anchored to the previous point in order to keep the spiral visually connected no matter how much the radius expands.

float px, py, x, y;
float theta;
float rotation;

void setup() {
  size(300, 300);
  px = py = x = y = theta = 0;
  rotation = 0.1;
  background(255);
}

void draw() {
  translate(width/2.0, height/2.0);
  x = theta*cos(theta/PI); 
  y = (theta)*sin(theta/PI);
  line(x, y, px, py);
  theta = theta + rotation;
  px = x;
  py = y;
  // check restart
  if (px>width/2.0) frameCount=-1;
}

with line segments, rotated

Uses the built-in rotate() and screenX() to rotate the frame of reference and then recover the rotated screen position of each next point. Draw each new line segments anchored to the previous point in order to keep the spiral visually connected no matter how much the radius expands.

float x, y, px, py;
float theta;
float rotation;

void setup() {
  size(300, 300);
  x = y = px = py = theta = 0;
  rotation = 0.1;
  background(255);
}

void draw() {
  // find coordinates with rotating reference frame
  pushMatrix();  
  rotate(theta/PI);
  x = screenX(theta, 0);
  y = screenY(theta, 0);
  popMatrix();

  translate(width/2.0, height/2.0);
  theta += rotation;
  line(px, py, x, y);
  px = x;
  py = y;
  if (theta>width/2.0) frameCount=-1; // start over
}

Processing Python mode

with points

When drawn with points the rotation must be very small, and initially the animation is very slow. This is because the points will move further and further apart as the radius increases.

theta = 0
rotation = 0.1

def setup():
    size(300, 300)
    background(255)

def draw():
    global theta
    translate(width / 2.0, height / 2.0)
    x = theta * cos(theta / PI)
    y = theta * sin(theta / PI)
    point(x, y)
    theta = theta + rotation
    # check restart
    if x > width / 2.0:
        background(255)
        theta = 0

Python

Using the turtle module.

from turtle import *
from math import *
color("blue")
down()
for i in range(200):
    t = i / 20 * pi
    x = (1 + 5 * t) * cos(t)
    y = (1 + 5 * t) * sin(t)
    goto(x, y)
up()
done()

Quackery

  [ $ "turtleduck.qky" loadfile ] now!
  turtle
  20 frames
  0 n->v 
  900 times 
    [ 2dup walk
      1 20 v+
      1 36 turn ]
  2drop
  1 frames
Output:

R

with(list(s=seq(0, 10 * pi, length.out=500)),
     plot((1 + s) * exp(1i * s), type="l"))

Racket

File:Archemedian-spiral-racket.png

#lang racket/base
(require plot
         racket/math)

;; x and y bounds set to centralise the circle
(define (archemedian-spiral-renderer2d a b θ/τ-max
                                       #:samples (samples (line-samples)))
  (define (f θ) (+ a (* b θ)))
  (define max-dim (+ a (* θ/τ-max 2 pi b)))
  (polar f
      0 (* θ/τ-max 2 pi)
      #:x-min (- max-dim)
      #:x-max max-dim
      #:y-min (- max-dim)
      #:y-max  max-dim
      #:samples samples))

(plot (list (archemedian-spiral-renderer2d 0.0 24  4)))

;; writes to a file so hopefully, I can post it to RC...
(plot-file (list (archemedian-spiral-renderer2d 0.0 24  4))
           "images/archemidian-spiral-racket.png")

Raku

(formerly Perl 6)

Works with: Rakudo version 2018.10
use Image::PNG::Portable;

my ($w, $h) = (400, 400);

my $png = Image::PNG::Portable.new: :width($w), :height($h);

(0, .025 ... 52*π).race.map: -> \Θ {
    $png.set: |((cis( Θ / π ) * Θ).reals »+« ($w/2, $h/2))».Int, 255, 0, 255;
}

$png.write: 'Archimedean-spiral-perl6.png';

REXX

This REXX version allows the user to specify (or override) the various constants used to calculate and display the spiral (plot).

Note:   the value of   a   doesn't mean that much as the plot is automatically centered.

/*REXX pgm plots several cycles (half a spiral) of the  Archimedean spiral (ASCII plot).*/
parse arg cy a b inc chr .                       /*obtain optional arguments from the CL*/
if  cy=='' |  cy==","   then  cy= 3              /*Not specified?  Then use the default.*/
if   a=='' |   a==","   then   a= 1              /* "      "         "   "   "     "    */
if   b=='' |   b==","   then   b= 9              /* "      "         "   "   "     "    */
if inc=='' | inc==","   then inc= 0.02           /* "      "         "   "   "     "    */
if chr=='' | chr==","   then chr= '∙'            /* "      "         "   "   "     "    */
if length(chr)==3  then chr= d2c(chr)            /*plot character coded in     decimal? */
if length(chr)==2  then chr= x2c(chr)            /*  "      "       "    " hexadecimal? */
cy= max(2, cy);         LOx= .                   /*set the  LOx  variable (a semaphore).*/
parse value scrsize()   with   sd  sw  .         /*get the size of the terminal screen. */
w= sw - 1        ;      mw= w * (cy-1) * 4       /*set useable width; max width for calc*/
h= sd - 1 + cy*10;      mh= h * (cy-1)           /* "     "    depth;  "  depth  "   "  */
@.=                                              /*initialize the line based plot field.*/
         do t=1  to pi()*cy  by inc              /*calc all the coördinates for spiral. */
         r= a +  b*    t                         /*  "   "   "       R       "    "     */
         x= w +  r*cos(t);     xx= x % 2         /*  "   "   "       X       "    "     */
         y= h +  r*sin(t);     yy= y % 2         /*  "   "   "       Y       "    "     */
         if x<0 | y<0 | x>mw | y>mh then iterate /*Is X or Y  out of bounds?  Then skip.*/
         if LOx==.  then do;   LOx= xx;      HIx= xx;      LOy= yy;       HIy= yy
                         end                     /* [↑]  find the minimums and maximums.*/
         LOx= min(LOx, xx);    HIx= max(HIx, xx) /*determine the   X   MIN  and  MAX.   */
         LOy= min(LOy, yy);    HIy= max(HIy, yy) /*    "      "    Y    "    "    "     */
         @.yy= overlay(chr, @.yy, xx+1)          /*assign the plot character (glyph).   */
         end   /*t*/
call plot                                        /*invoke plotting subroutine (to term).*/
exit                                             /*stick a fork in it,  we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
pi:   pi=3.1415926535897932384626433832795028841971693993751058209749445923078; return pi
plot:      do row=HIy  to LOy  by -1;   say substr(@.row, LOx+1);   end;        return
r2r:  return arg(1)  //  (pi() * 2)             /*normalize radians ───► a unit circle.*/
/*──────────────────────────────────────────────────────────────────────────────────────*/
cos:  procedure; parse arg x;  x= r2r(x);  _= 1;  a= abs(x);    hpi= pi * .5
      numeric fuzz  min(6, digits() - 3);         if a=pi       then return -1
      if a=hpi | a=hpi*3  then return  0          if a=pi / 3   then return .5
      if a=pi * 2 / 3     then return -.5;        q= x*x;       z= 1
        do k=2  by 2  until p=z;   p= z;   _= -_ *q/(k*k-k);    z= z+_;   end;    return z
/*──────────────────────────────────────────────────────────────────────────────────────*/
sin:  procedure; parse arg x;  x= r2r(x);  _= x;  numeric fuzz min(5, max(1, digits() -3))
      if x=pi * .5         then return 1;         if x==pi*1.5  then return -1
      if abs(x)=pi | x=0   then return 0;         q= x*x;       z= x
        do k=2  by 2  until p=z;   p= z;   _= -_ *q/(k*k+k);    z= z+_;   end;    return z
output   when using the following inputs:     13   ,   5   ,   db

(Output is shown at   1/20   size.)

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Ring

/*
 +---------------------------------------------------------------------------------------------------------
 +     Program Name : Archimedean spiral
 +---------------------------------------------------------------------------------------------------------
*/
Load "guilib.ring"

horzSize  = 400
vertSize  = 400 

counter     = 0  ### cycle thru colors       
colorRed    = new qcolor() { setrgb(255,000,000,255) }
colorGreen  = new qcolor() { setrgb(000,255,000,255) }
colorBlue   = new qcolor() { setrgb(000,000,255,255) }
colorYellow = new qcolor() { setrgb(255,255,000,255) }

penUseR = new qpen() { setcolor(colorRed)    setwidth(1) }
penUseG = new qpen() { setcolor(colorGreen)  setwidth(1) }
penUseB = new qpen() { setcolor(colorBlue)   setwidth(1) }
penUseY = new qpen() { setcolor(colorYellow) setwidth(1) }

        deg2rad    = atan(1) * 4 / 180  
        screensize = 600                 
        turns      = 5                
        halfscrn   = screensize / 2    
        sf         = (turns * (screensize - 100)) / halfscrn 
        x = 1
        y = 1
        r = 0
        inc = 0.50   ### control increment speed of r
        
New qapp
{
   win1 =  new qwidget()
    {
        setwindowtitle("Draw Spiral")
        setgeometry(100,100,600,600)
       
       label1 = new qlabel(win1)
       {
           setgeometry(10,10,600,600)
           settext("")
       }
       
       
       Canvas = new qlabel(win1)
       {              
            MonaLisa = new qPixMap2( 600,600)  
            color    = new qcolor(){ setrgb(255,0,0,255) }

            daVinci  = new qpainter() 
            {
               begin(MonaLisa)             
               penUse = new qpen() { setcolor(colorRed) setwidth(1) }
               setpen(penUseR)
               #endpaint()      ### This will Stop the Painting
            }
            
            setpixmap(MonaLisa)        
       }       
     
        oTimer = new qTimer(win1) 
        {
            setinterval(1)    ### 1 millisecond
            settimeoutevent("DrawCounter()")
            start()
        }       
                
       show()   ### Will show Painting ONLY after exec   
    }
   exec()
}


###====================================================

Func DrawCounter()

    x  = cos(r * deg2rad) * r / sf 
    y  = sin(r * deg2rad) * r / sf
    r += inc   ###  0.20 fast, 0.90 slow

        if r >= turns * 360
            r = inc 
            x = 1 
            y = 1   
            counter++
            whichColor = counter % 4
            See  "whichColor: "+ whichColor +nl

                if whichColor = 0 daVinci.setpen(penUseR)  ok
                if whichColor = 1 daVinci.setpen(penUseG)  ok
                if whichColor = 2 daVinci.setpen(penUseB)  ok
                if whichColor = 3 daVinci.setpen(penUseY)  ok
 ok

    hpoint = halfscrn + x
    ypoint = halfscrn - y

    daVinci.drawpoint(hpoint, ypoint)  
    Canvas.setpixmap(MonaLisa)          ### Need this setpixmap to display imageLabel
    win1.show()                         ### Need this show to display imageLabel
    
return

RPL

File:Archimedean.png
HP-48G emulator screenshot
Works with: HP version 48G
« → a b
 « -20 20 DUP2 XRNG YRNG
   POLAR RAD 'a+b*t' STEQ { t 0 18.9 } INDEP
   ERASE DRAW { } PVIEW 
   { EQ PPAR } PURGE
» » 'ARCHI' STO
1 1 ARCHI

Ruby

Library: RubyGems
Library: JRubyArt

JRubyArt is an implementation of Processing in ruby, that uses JRuby to provide the interoperability with the java libraries.

INCR = 0.1
attr_reader :x, :theta

def setup
  sketch_title 'Archimedian Spiral'
  @theta = 0
  @x = 0
  background(255)
  translate(width / 2.0, height / 2.0)
  begin_shape
  (0..50*PI).step(INCR) do |theta|
    @x = theta * cos(theta / PI)
    curve_vertex(x, theta * sin(theta / PI))
  end
  end_shape
end

def settings
  size(300, 300)
end

Rust

#[macro_use(px)]
extern crate bmp;

use bmp::{Image, Pixel};
use std::f64;

fn main() {
    let width = 600u32;
    let half_width = (width / 2) as i32;
    let mut img = Image::new(width, width);
    let draw_color = px!(255, 128, 128);

    // Constants defining the spiral size.
    let a = 1.0_f64;
    let b = 9.0_f64;

    // max_angle = number of spirals * 2pi.
    let max_angle = 5.0_f64 * 2.0_f64 * f64::consts::PI;

    let mut theta = 0.0_f64;
    while theta < max_angle {
        theta = theta + 0.002_f64;

        let r = a + b * theta;
        let x = (r * theta.cos()) as i32 + half_width;
        let y = (r * theta.sin()) as i32 + half_width;
        img.set_pixel(x as u32, y as u32, draw_color);
    }

    // Save the image
    let _ = img.save("archimedean_spiral.bmp").unwrap_or_else(|e| panic!("Failed to save: {}", e));
}

SAS

data xy;
h=constant('pi')/40;
do i=0 to 400;
    t=i*h;
    x=(1+t)*cos(t);
    y=(1+t)*sin(t);
    output;
end;
keep x y;
run;

proc sgplot;
series x=x y=y;
run;

Scala

Java Swing Interoperability

object ArchimedeanSpiral extends App {

  SwingUtilities.invokeLater(() =>
    new JFrame("Archimedean Spiral") {

      class ArchimedeanSpiral extends JPanel {
        setPreferredSize(new Dimension(640, 640))
        setBackground(Color.white)

        private def drawGrid(g: Graphics2D): Unit = {
          val (angle, margin, numRings) = (toRadians(45), 10, 8)
          val w = getWidth
          val (center, spacing) = (w / 2, (w - 2 * margin) / (numRings * 2))

          g.setColor(new Color(0xEEEEEE))
          for (i <- 0 until numRings) {
            val pos = margin + i * spacing
            val size = w - (2 * margin + i * 2 * spacing)
            g.drawOval(pos, pos, size, size)
            val ia = i * angle
            val x2 = center + (cos(ia) * (w - 2 * margin) / 2).toInt
            val y2 = center - (sin(ia) * (w - 2 * margin) / 2).toInt
            g.drawLine(center, center, x2, y2)
          }
        }

        private def drawSpiral(g: Graphics2D): Unit = {
          val (degrees: Double, center) = (toRadians(0.1), getWidth / 2)
          val (a, b, c, end) = (0, 20, 1, 360 * 2 * 10 * degrees)

          def plot(g: Graphics2D, x: Int, y: Int): Unit = g.drawOval(x, y, 1, 1)

          def iter(theta: Double): Double = {
            if (theta < end) {
              val r = a + b * pow(theta, 1 / c)
              val x = r * cos(theta)
              val y = r * sin(theta)
              plot(g, (center + x).toInt, (center - y).toInt)
              iter(theta + degrees)
            } else theta
          }

          g.setStroke(new BasicStroke(2))
          g.setColor(Color.orange)
          iter(0)
        }

        override def paintComponent(gg: Graphics): Unit = {
          super.paintComponent(gg)
          val g = gg.asInstanceOf[Graphics2D]
          g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON)
          drawGrid(g)
          drawSpiral(g)
        }
      }

      add(new ArchimedeanSpiral, BorderLayout.CENTER)
      pack()
      setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE)
      setLocationRelativeTo(null)
      setResizable(false)
      setVisible(true)
    }
  )

}

Scheme

Library: Scheme/PsTk
(import (scheme base)
        (scheme complex) 
        (rebottled pstk))

; settings for spiral
(define *resolution* 0.01)
(define *count* 2000)
(define *a* 10)
(define *b* 10)
(define *center* 
  (let ((size 200)) ; change this to alter size of display
    (* size 1+i)))

(define (draw-spiral canvas)
  (define (coords theta)
    (let ((r (+ *a* (* *b* theta))))
      (make-polar r theta)))
  ;
  (do ((i 0 (+ i 1))) ; loop to draw spiral
    ((= i *count*) )
    (let ((c (+ (coords (* i *resolution*)) *center*)))
      (canvas 'create 'line 
              (real-part c) (imag-part c)
              (+ 1 (real-part c)) (imag-part c)))))

(let ((tk (tk-start)))
  (tk/wm 'title tk "Archimedean Spiral")
  (let ((canvas (tk 'create-widget 'canvas)))
    (tk/pack canvas)
    (canvas 'configure 
            'height: (* 2 (real-part *center*)) 
            'width: (* 2 (imag-part *center*)))
    (draw-spiral canvas))
  (tk-event-loop tk))

Scilab

a = 3;
b = 2;

theta = linspace(0,10*%pi,1000);
r = a + b .* theta;

//1. Plot using polar coordinates
scf(1);
polarplot(theta,r);

//2. Plot using rectangular coordinates
//2.1 Convert coordinates using Euler's formula
z = r .* exp(%i .* theta);
x = real(z);
y = imag(z);

scf(2);
plot2d(x,y);

Seed7

$ include "seed7_05.s7i";
  include "draw.s7i";
  include "keybd.s7i";

const proc: main is func
  local
    const float: xCenter is 117.0;
    const float: yCenter is 139.0;
    const float: maxTheta is 10.0 * PI;
    const float: delta is 0.01;
    const float: a is 1.0;
    const float: b is 7.0;
    var float: theta is 0.0;
    var float: radius is 0.0;
  begin
    screen(256, 256);
    clear(curr_win, black);
    KEYBOARD := GRAPH_KEYBOARD;
    while theta <= maxTheta do
      radius := a + b * theta;
      point(round(xCenter + radius * cos(theta)),
            round(yCenter - radius * sin(theta)), white);
      theta +:= delta;
    end while;
    DRAW_FLUSH;
    ignore(getc(KEYBOARD));
  end func;

Sidef

Translation of: Raku
require('Imager')
define π = Num.pi

var (w, h) = (400, 400)
var img = %O<Imager>.new(xsize => w, ysize => h)

for Θ in (0 .. 52*π -> by(0.025)) {
    img.setpixel(
        x => floor(cos(Θ / π)*Θ + w/2),
        y => floor(sin(Θ / π)*Θ + h/2),
        color => [255, 0, 0]
    )
}

img.write(file => 'Archimedean_spiral.png')

Output image: Archimedean spiral

Stata

clear all
scalar h=_pi/40
set obs 400
gen t=_n*h
gen x=(1+t)*cos(t)
gen y=(1+t)*sin(t)
line y x

Tcl

This creates a little Tk GUI where you can interactively enter values for `a` and `b`. The spiral will be re-drawn automatically thanks to `trace`:

package require Tk

# create widgets
canvas .canvas
frame .controls

ttk::label .legend -text " r = a + b θ "
ttk::label .label_a -text "a ="
ttk::entry .entry_a -textvariable a
ttk::label .label_b -text "a ="
ttk::entry .entry_b -textvariable b
button .button -text "Redraw" -command draw

# layout
grid .canvas .controls -sticky nsew
grid .legend - -sticky ns -in .controls
grid .label_a .entry_a -sticky nsew -in .controls
grid .label_b .entry_b -sticky nsew -in .controls
grid .button - -sticky ns -in .controls

# make the canvas resize with the window
grid columnconfigure . 0 -weight 1
grid rowconfigure . 0 -weight 1

# spiral parameters:
set a .2
set b .05

proc draw {} {
    variable a
    variable b

    # make sure inputs are valid:
    if {![string is double $a] || ![string is double $b]} return
    if {$a == 0 || $b == 0} return

    set w [winfo width .canvas]
    set h [winfo height .canvas]
    set r 0
    set pi [expr {4*atan(1)}]
    set step [expr {$pi / $w}]
    for {set t 0} {$r < 2} {set t [expr {$t + $step}]} {
        set r [expr {$a + $b * $t}]
        set y [expr {sin($t) * $r}]
        set x [expr {cos($t) * $r}]

        # transform to canvas co-ordinates
        set y [expr {entier((1+$y)*$h/2)}]
        set x [expr {entier((1+$x)*$w/2)}]
        lappend coords $x $y
    }
    .canvas delete all
    set id [.canvas create line $coords -fill red]
}

# draw whenever parameters are changed
# ";#" so extra trace arguments are ignored
trace add variable a write {draw;#}
trace add variable b write {draw;#}

wm protocol . WM_DELETE_WINDOW exit ;# exit when window is closed

update  ;# lay out widgets before trying to draw
draw
vwait forever ;# go into event loop until window is closed

Wren

Translation of: Sidef
Library: DOME
import "graphics" for Canvas, Color
import "dome" for Window

class Game {
    static init() {
        Window.title = "Archimedean Spiral"
        __width = 400
        __height = 400
        Canvas.resize(__width, __height)
        Window.resize(__width, __height)
        var col = Color.red
        spiral(col)
    }

    static spiral(col) {
        var theta = 0
        while (theta < 52 * Num.pi) {
            var x = ((theta/Num.pi).cos * theta + __width/2).truncate
            var y = ((theta/Num.pi).sin * theta + __height/2).truncate
            Canvas.pset(x, y, col)
            theta = theta + 0.025
        }
    }

    static update() {}

    static draw(dt) {}
}
Output:

File:Wren-Archimedean spiral.png

XPL0

Looks a lot like the C++ image.

real A, B, R, T, X, Y;
[SetVid($12);           \set 640x480 graphics
A:= 0.0;  B:= 3.0;  T:= 0.0;
Move(320, 240);         \start at center of screen
repeat  R:= A + B*T;
        X:= R*Cos(T);  Y:= R*Sin(T);
        Line(fix(X)+320, 240-fix(Y), 4\red\);
        T:= T + 0.03;   \increase angle (Theta)
until   T >= 314.159;   \50 revs
]

zkl

Uses the PPM class from http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm#zkl

fcn archimedeanSpiral(a,b,circles){
   w,h:=640,640; centerX,centerY:=w/2,h/2;
   bitmap:=PPM(w+1,h+1,0xFF|FF|FF);  // White background

   foreach deg in ([0.0 .. 360*circles]){
      rad:=deg.toRad();
      r:=rad*b + a;
      x,y:=r.toRectangular(rad);
      bitmap[centerX + x, centerY + y] = 0x00|FF|00;  // Green dot
   }
   bitmap.writeJPGFile("archimedeanSpiral.jpg");
}(0,5,7);