Transferred from en.wikipedia to Commons by Maksim.

File:Normal subgroup illustration.svg是本檔案的向量版本。 如果品質不低，就應該優先使用該檔案，而非PNG檔案。 File:Normal subgroup illustration.png → File:Normal subgroup illustration.svg 更多資訊請參閱Help:SVG/zh。 其他語言 Alemannisch ∙ Bahasa Indonesia ∙ Bahasa Melayu ∙ British English ∙ català ∙ čeština ∙ dansk ∙ Deutsch ∙ eesti ∙ English ∙ español ∙ Esperanto ∙ euskara ∙ français ∙ Frysk ∙ galego ∙ hrvatski ∙ Ido ∙ italiano ∙ lietuvių ∙ magyar ∙ Nederlands ∙ norsk bokmål ∙ norsk nynorsk ∙ occitan ∙ Plattdüütsch ∙ polski ∙ português ∙ português do Brasil ∙ română ∙ Scots ∙ sicilianu ∙ slovenčina ∙ slovenščina ∙ suomi ∙ svenska ∙ Tiếng Việt ∙ Türkçe ∙ vèneto ∙ Ελληνικά ∙ беларуская (тарашкевіца) ∙ български ∙ македонски ∙ нохчийн ∙ русский ∙ српски / srpski ∙ татарча/tatarça ∙ українська ∙ ქართული ∙ հայերեն ∙ বাংলা ∙ தமிழ் ∙ മലയാളം ∙ ไทย ∙ 한국어 ∙ 日本語 ∙ 简体中文 ∙ 繁體中文 ∙ עברית ∙ العربية ∙ فارسی ∙ +/−

 

摘要

Made by myself with Matlab

授權條款

我，此作品的版權所有人，釋出此作品至公共領域。此授權條款在全世界均適用。 這可能在某些國家不合法，如果是的話： 我授予任何人有權利使用此作品於任何用途，除受法律約束外，不受任何限制。

Source code

function main ()

N=12; line_thickness=2.2; font_size=25; d=0.13; big_rad=10; ball_rad=0.5; ii=sqrt(-1);
red=[1, 0, 0]; green=[0, 1, 0]; blue=[0, 0, 1];
All=[red' green' blue'];

figure(1); clf; hold on; axis equal; axis off;

Theta=0:0.1:3*pi;
X=big_rad*cos(Theta);
Y=big_rad*sin(Theta);
plot(X, Y, 'linewidth', line_thickness, 'color', [0 0 0]);

for i=0:(N-1)
   z=big_rad*exp(i*ii*2*pi/N);
   place_text_smartly (z, font_size, i, d, sprintf('%d\\pi/%d', i, N/2), N);
   color_ball(real(z), imag(z), ball_rad, All(:, mod(i, 3)+1)');
end

scale=1.4;plot(scale*big_rad,  scale*big_rad)
scale=-1.4;plot(scale*big_rad,  scale*big_rad)

saveas(gcf, 'Normal_subgroup_illustration.eps', 'psc2')
saveas(gcf, 'Normal_subgroup_illustration.png')

function place_text_smartly (z, font_size, pos, d, tx, N)
 p=cos(2*pi/N)+sqrt(-1)*sin(2*pi/N);
 z = z + p^pos * d * font_size;
 shiftx=0.0003; shifty=0.03;
 x = real (z); y=imag(z);
 H=text(x+shiftx*font_size, y+shifty*font_size, tx);
 set(H, 'fontsize', font_size, 'HorizontalAlignment', 'c', 'VerticalAlignment', 'c')

 function color_ball(x, y, r, color)
    Theta=0:0.1:2*pi;
    X=r*cos(Theta)+x;
    Y=r*sin(Theta)+y;
    H=fill(X, Y, color);
    set(H, 'EdgeColor', 'none');

原始上傳日誌

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) 13:18, 27 October 2005 . . en:User:Oleg_Alexandrov Oleg Alexandrov ( en:User_talk:Oleg_Alexandrov Talk) . . 648x623 (49214 bytes) (Made by myself with Matlab.)