# Error: LaTeX Xy-pic error: <turn> cannot be half or full… What does it mean?

I'm attempting to use xy to make an arrow bend a specific way. When I try it, this error pops up:

LaTeX Xy-pic error: < turn > cannot be half or full.

What does this mean?

For more context, I am attempting to make this:

\xymatrix@!R@!C
{
&   &   &   & \bullet & &   &   &   \\
\\
\bullet &   &   &   & \bullet & &   &   & \bullet \\
\\
&   & \bullet & &   &   &   &   &   \\
\\
&   &   & \bullet & & \bullet & & \bullet & \\
\\
& \bullet \ar@{-}@/^1pc/ [uuuuuul] \ar@{-} u[uuuu][uuuur] &    & \bullet \ar@{-}     l[ul][uuuul] \ar@{-}@/_/ [uuuuuur] & & \bullet & &   &   \\
\\
&   &   &   &   &   & \bullet \ar@{-}@/^3pc/[uuuulll] \ar@{-    }@/_1pc/[uuuul] \ar@{-} ^u [r] [uuuur] &   &   \\
\\
\bullet \ar@{-} u [uuuuuu][uuuuuurrr] \ar@{-}[uuuur] \ar@{-}[uuuurrr] \ar@{-}    [uuuurrrrr] & &   &   & \bullet \ar@{-} @/^1pc/[uuuuuur] \ar@{-}[uuuur] & &       &   & \bullet \ar@{-}@/^3pc/ [uuuulll] \ar@{-}@/_/ [uuuuuul] \\
\\
&   &   &   & \bullet \ar@{-}[uullll] \ar@{-}[uu] \ar@{-}[uuuurr]     \ar@{-}[uurrrr] & &   &   &   \\
}


This has 8 rows in it. If you look at the 5th row from the top, there are three bullets (oriented kind of to the left). The middle bullet needs to go out to the left 1 space, turn to the right then go up 4 spaces. However, this never works and I keep getting this error. Oddly enough, if I type in other variations, it DOES work. It just doesn't look like the diagram I need to make. For example, I can go

\ar@{-} '^u[uuuu][uuuul]


and it will go up first and THEN curve to the left or I can go

\ar@{-} 'r[r][uuuul]


and it will also work but be completely wrong. It seems to only fail when I go to the left.

Why?? I assume the error code could help me understand this further.

EDIT: Now when I attempt to compile this, I get the error message:

Xy-pic error: in entry "9,4": No [ul] (is "8,3") from here.

• Could you please edit your post and make your code fully compilable? It would help solvers to start working on it. – Malipivo Apr 17 '14 at 3:57
• @Malipivo good advice. Done! – Bark Jr. Apr 17 '14 at 14:06
• @BarkJr. A compilable code should start with \documentclass{ and end with \end{document}. Like this, we have to guess, what you are doing. – LaRiFaRi Apr 17 '14 at 14:08

To be honest, I don't know, what is happening with your approach, but would this image be ok for you?

% arara: pdflatex

\documentclass{standalone}
\usepackage[all]{xy}
\xyoption{pdf}

\begin{document}
\xymatrix@!R@!C
{
& & & & {\bullet} & & & & \\
\\
{\bullet} & & & & {\bullet} & & & & {\bullet} \\
\\
& & {\bullet} \ar@{-} d [ddddr][ddddr] & & & & & &  \\
\\
& & & {\bullet} & & {\bullet} & & {\bullet} & \\
\\
& {\bullet} \ar@{-}@/^1pc/ [uuuuuul] \ar@{-} u[uuuu][uuuur] & & {\bullet} \ar@{-}@/_/ [uuuuuur]& & {\bullet} & & & \\
\\
& & & & & & {\bullet} \ar@{-}@/^3pc/[uuuulll] \ar@{-}@/_1pc/[uuuul] \ar@{-} ^u [r] [uuuur] & & \\
\\
{\bullet} \ar@{-} u [uuuuuu][uuuuuurrr] \ar@{-}[uuuur] \ar@{-}[uuuurrr] \ar@{-} [uuuurrrrr] & & & & {\bullet} \ar@{-} @/^1pc/[uuuuuur] \ar@{-}[uuuur] & &  &  & {\bullet} \ar@{-}@/^3pc/ [uuuulll] \ar@{-}@/_/ [uuuuuul] \\
\\
& & & & {\bullet} \ar@{-}[uullll] \ar@{-}[uu] \ar@{-}[uuuurr] \ar@{-}[uurrrr] & & & & \\
}
\end{document}

• Yes! That worked. I see what you did: you went [dddr] instead of [uuuul]. I don't know why that never occurred to me. – Bark Jr. Apr 17 '14 at 15:17