Image:Archimedean spiral.png
From Wikipedia, the free encyclopedia
Archimedean_spiral.png (10KB, MIME type: image/png
)
This is a file from the Wikimedia Commons. The description on its description page there is shown below. |
A vector version of this image ("SVG") is available, and should be used in place of this raster image when superior. For more information about vector graphics, read about Commons transition to SVG. There is also information about MediaWiki's support of SVG images. |
eo: La bildo estas kopiita de wikipedia:en. La originala priskribo estas:
Contents |
[edit] Summary
Three 360° turnings of one arm of an Archimedean spiral (higher-resolution picture). Produced with the following PostScript code:
%! .75 setgray 2 setlinewidth 280 640 moveto 0 -540 rlineto stroke 16 396 moveto 580 0 rlineto stroke 1 0 0 setrgbcolor %%%%%%%%%%%%%%%% % PostScript program to display an Archimedean spiral by approximating % it with Bezier curves. Can display a double spiral (two spirals % rotated by 180 degrees with respect to each other). %%% Parameters: /sepwid 100 def % width separating successive turnings of spiral % (half this if double spiral is selected) /incrm 11.25 def % insert a curve point after this number of degrees /sweeps 3 def % number of 360 degree turnings to show /centerx 280 def % horizontal coordinate of center of spiral /centery 396 def % vertical coordinate of center of spiral /double 0 def % change to 1 to display double spiral /linew 3 def % increase number for thicker line %%% Procedures: /pi 3.1415926535898 def/radians 57.295779513082 def /sepwid sepwid pi div 2 div def gsave centerx centery translate linew setlinewidth /aspiral{/prevbezy 0 def 0 0 moveto 0 incrm sweeps 360 mul{7{dup}repeat phase add cos/costh exch def phase add sin/sinth exch def costh mul radians div/thcosth exch def sinth mul radians div/thsinth exch def thcosth sepwid mul/x exch def thsinth sepwid mul/y exch def /slope sinth thcosth add costh thsinth sub div def sinth 0 gt sinth 0 eq costh -1 eq and or{/flag -1 def}{/flag 1 def}ifelse /A exch def A 49.29348 lt A 180 gt A 196.273450852 lt and A 360 gt A 368.8301 lt and A 540 gt A 545.9907 lt and A 720 gt A 724.5217 lt and A 900 gt A 903.6281968 lt and or or or or or{/flag flag neg def}if incrm sub 3{dup}repeat phase add cos sepwid mul mul radians div /prevx exch def phase add sin sepwid mul mul radians div /prevy exch def incrm add 3{dup}repeat phase add cos sepwid mul mul radians div /nextx exch def phase add sin sepwid mul mul radians div /nexty exch def /prevdist x prevx sub dup mul y prevy sub dup mul add sqrt pi div def /nextdist x nextx sub dup mul y nexty sub dup mul add sqrt pi div def /normaliz slope slope mul 1 add sqrt def 0 eq{/prevbezx phase cos nextdist mul def}{prevbezx prevbezy x 1 flag mul normaliz div prevdist mul sub y slope flag mul normaliz div prevdist mul sub x y curveto /prevbezx x 1 flag mul normaliz div nextdist mul add def /prevbezy y slope flag mul normaliz div nextdist mul add def}ifelse} for stroke}def /phase 0 def aspiral %%% If different sweeps parameter for second spiral, define here: %%%%%%%%%%%%%%%% double 0 ne{/phase 180 def aspiral}if grestore showpage %%EOF
[edit] Licensing
This image has been released into the public domain by its author, AnonMoos. This applies worldwide. In some countries this may not be legally possible; if so: |
[edit] Edit history on en.wikipedia
date/time | username | edit summary |
---|---|---|
22:42, 20 November 2005 | en:User:AnonMoos | (update description to reflect new version of image) |
23:05, 16 November 2005 | en:User:AnonMoos | (add category) |
12:59, 23 October 2005 | en:User:AnonMoos | (tweaking) |
02:16, 23 October 2005 | en:User:AnonMoos | →Summary |
01:40, 23 October 2005 | en:User:AnonMoos | |
01:38, 23 October 2005 | en:User:AnonMoos | (tags) |
01:20, 23 October 2005 | en:User:AnonMoos | (One arm of an Archimedean spiral (higher-resolution picture). Produced with the following PostScript code: .75 setgray 2 setlinewidth 280 640 moveto 0 -540 rlineto stroke 16 396 moveto 580 0 rlineto stroke 1 0 0 setrgbcolor 1 setlinecap %%%%%) |
[edit] Upload history on en.wikipedia
Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version.
Click on date to download the file or see the image uploaded on that date.
- (del) (cur) 22:38, 20 November 2005 . . en:User:AnonMoos AnonMoos ( en:User_talk:AnonMoos Talk) . . 656x600 (9955 bytes) (larger slightly-corrected version)
- (del) (rev) 01:20, 23 October 2005 . . en:User:AnonMoos AnonMoos ( en:User_talk:AnonMoos Talk) . . 600x550 (9150 bytes) (One arm of an Archimedean spiral (higher-resolution picture). Produced with the following PostScript code: <nowiki> %! .75 setgray 2 setlinewidth 280 640 moveto 0 -540 rlineto stroke 16 396 moveto 580 0 rlineto stroke 1 0 0 setrgbcolor 1 setlinecap %%%%%)
File links
The following pages on the English Wikipedia link to this file (pages on other projects are not listed):