Asymptote FAQ - Section 3
Questions about paths

• Q3.1. Why do I get a syntax error message when I specify an integer value for the path tension?
• Q3.2. Shouldn't dots always be the same size?

Question 3.1. Why do I get a syntax error message when I specify an integer value for the path tension?

draw((0,0)..tension 2..(0,50)..(100,100));

draw((0,0)..tension 2. .(0,50)..(100,100));

draw((0,0)..tension 2 ..(0,50)..(100,100));

Question 3.2. Shouldn't dots always be the same size?

"The dot command defined in the module plain draws a dot having a diameter equal to an explicit pen linewidth or the default linewidth magnified by dotfactor (6 by default)."

Thus, when you use the default pen, the dot will have size 6*linewidth, but when you give a pen with an explicit width specified, you will have a dot of size linewidth. If you want the first case to behave like the second, you may set dotfactor=1.