# How to make colored labels in feynMF/feynMP

There are several ways of adding a label to the vertex, e.g. as in code below. It is documented how to make the colored polygons or lines, as done for the V2, but I couldn't find anything about making the label coloured. Is it possible in the feynMP package?

\begin{fmffile}{feyngraph}
\begin{fmfgraph*}(150,80)

\fmfleft{i1,i2}
\fmfright{o1,o2}

\fmf{fermion}{i1,v1}
\fmf{fermion}{v1,i2}
\fmf{fermion}{v2,o1}
\fmf{fermion}{o2,v2}
\fmf{photon}{v1,v2}

% first vertex
\fmfdot{v1}
\fmflabel{V1}{v1}

% second vertex
\fmfv{d.sh=circle, d.fi=full, d.si=2thick, f=(1,,0,,0), l=V2}{v2}

\end{fmfgraph*}
\end{fmffile}


Result of the code:

• Did you try \fmflabel{\textcolor{red}{V1}}{v1}? – Sigur Jan 8 '15 at 13:26
• @Sigur great, it worked! Thanks you very much. Put it into the answer so that I can accept it... – BartoNaz Jan 8 '15 at 13:27
• Nice! Let's wait for a more professional solution. I'm almost sure that it does exist. – Sigur Jan 8 '15 at 13:29
• How to move the position of labelling? What if I want it on other side of vertex or fermion? – Love Grover Feb 16 '16 at 13:46