Since this question doesn't have an answer yet, I've been trying to take matters into my own hands. My aim is a sine curve which fades from nothing on the left, to bold on the right.
Preferably I would use the fadings library for this:
\draw [domain=-2:2, path fading=west] plot (\x, {(1/15) * sin(18*\x r)});
But for some reason that doesn't work. If any one knows why not, that would be great but that's the topic of the question I linked above.
So I thought I'd do the fading myself with the following loop:
\foreach \x/\opac in {0.5/0.1, 1/0.2, 1.5/0.3, 2/0.4} {
\draw [domain=\x:\x+0.5, ultra thick, opacity=\opac]
plot (\x, {(1/15) * sin(18*\x r)}); }
But if you try this you'll see that the different plots don't match up perfectly at the end/beginning of the domains. There are overlaps and underlaps which mean this looping method isn't working for me to make a fake fading. Anybody know why this is? The problem seems to be essentially the angles of the beginning and end of the plotted lines aren't consistent.
\begin{document}and\begin{tikzpicture}and similarly at the end. What's in the question is the entirety of the drawing. What's wrong with\x? It's a traditional name for a variable in an equation, and the name of a direction/axis. In this case it represents both. – thosphor Nov 11 '16 at 16:25