Asymptote FAQ - Section 4
Questions about labels

• Q4.1. How do I get Greek letters like omega to show up in my labels?
• Q4.2. Can Asymptote use matrices as labels?
• Q4.3. How do I tell Asymptote to load a particular LaTeX package, like mathptmx?
• Q4.4. How can I use international fonts in Asymptote labels?
• Q4.5. How can I use Fourier fonts?
• Q4.6. Is there any way to change the default appearance of the decimal separator, using a comma instead of a dot?
• Q4.7. How can I get a rotated label with the filled box rotated as well so that it fits the text?
• Q4.8. How can I rotate labels in a 3D figure?
• Q4.9. How can I draw some squares and circles of a fixed size and put a label in the middle of them?
• Q4.10. The binary operator * can be used to scale the color of a pen by a real number. Does this scaling factor have to be less than 1?
• Q4.11. Why is the space after the comma decimal separator in my locale so large?
• Q4.12. How can I prevent texpreamble("\usepackage[pdftex]{hyperref}") from changing the page size?

Question 4.1. How do I get Greek letters like omega to show up in my labels?

label("$\omega$",(0,0));
label("$\Omega$",(20,0));

Question 4.2. Can Asymptote use matrices as labels?

usepackage("amsmath");
label("$\begin{matrix} 1 & 2 \\\ 1 & 1 \end{matrix}$",(0,0));

Question 4.3. How do I tell Asymptote to load a particular LaTeX package, like mathptmx?

usepackage("mathptmx");

defaultpen(TimesRoman());

Question 4.4. How can I use international fonts in Asymptote labels?

Question 4.5. How can I use Fourier fonts?

usepackage("fourier");
defaultpen(font("T1","fut\textfamilyextension","m","n"));

Question 4.6. Is there any way to change the default appearance of the decimal separator, using a comma instead of a dot?

locale("it_IT");
usepackage("icomma");
label(format(0.5));

Question 4.7. How can I get a rotated label with the filled box rotated as well so that it fits the text?

frame f;
label(f,"This is some text",white,Fill(blue));
add(rotate(65)*f);

Question 4.8. How can I rotate labels in a 3D figure?

import three;
size(100,100);

draw(rotate(90,project(Z))*"A",O--X);

Question 4.9. How can I draw some squares and circles of a fixed size and put a label in the middle of them?

real u=2cm;
 
picture square;
draw(square,scale(u)*shift(-0.5,-0.5)*unitsquare);
 
picture circle;
draw(circle,scale(0.5u)*unitcircle);
 
void add(picture pic=currentpicture, Label L, picture object, pair z) { 
add(pic,object,z);
label(pic,L,z);
} 
 
add("square",square,(0,0));
add("circle",circle,(5cm,0));

Question 4.10. The binary operator * can be used to scale the color of a pen by a real number. Does this scaling factor have to be less than 1?

Try

write(cyan); write(0.8*cyan); write(1.5*cyan);

To get a lighter cyan you can say white+cyan, which yields rgb(0.5,1,1). If you want something even lighter specify the rgb colors directly, for example, rgb(0.9,1,1).

Alternatively, work in cmyk colour space, which is nicer in that it handles saturation separately from hue:

0.1*Cyan is light and 0.9*Cyan is dark. You can also say 0.1*cmyk(red).

Question 4.11. Why is the space after the comma decimal separator in my locale so large?

usepackage("icomma");

Question 4.12. How can I prevent texpreamble("\usepackage[pdftex]{hyperref}") from changing the page size?

texpreamble("\usepackage[pdftex,setpagesize=false]{hyperref}");