I'm trying to make a diagram with arrows returning to the same entry using xymatrix
. The following example works perfectly fine.
\[
\xymatrix{
V \ar@(dl,ul)[]^{h'} \ar@<0.5ex>[r]^{i} & W \ar@(dr,ur)[]_{h} \ar@<0.5ex>[l]^{p}
},
\]
However, if I try to change V
to (V,d_V)
, I only get error messages.
I tried already to place it into {}
, but it makes no difference. Typing
\[
\xymatrix{
{(V,d_V)} \ar@(dl,ul)[]^{h'} \ar@<0.5ex>[r]^{i} & {(W,d_W)} \ar@(dr,ur)[]_{h} \ar@<0.5ex>[l]^{p}
},
\]
I still get error messages like
! Undefined control sequence.
\splineendScan@ ...s@ \expandafter {\splineedges@
}\xylowtolerance@ \splined...
I hope someone can help me.