# If condition controlled with a loop variable

I want to print some images according to a variable being changed in a loop: if variable group is 1, then the image should not be printed. But if the value of group is 2, then the image should be printed. So I am looking for sort of an "if" condition.

I have already looked at the if conditions in LaTeX but I am not finding a solution that fits my case (controlling the if with a variable which is changing in a loop).

\newcounter{group}
\newcounter{subj}
\newcounter{number_of_runs_simona}
\forloop{group}{1}{\value{group} < 2}{
\forloop{subj}{1}{\value{subj} < 2}{
\forloop{number_of_runs_simona}{1}{\value{number_of_runs} < 26}{
\centering

\textbf{\large Group \arabic{group}, Subject \arabic{subj}, Run \arabic{number_of_runs}}

\begin{figure}[!ht]
\centering
\includegraphics{\FILENAMEONE{\arabic{group}}{\arabic{subj}}{\arabic{number_of_runs_simona}}}
\end{figure}

\clearpage
}
}
}


Figure "FILENAMEONE" should only be printed when the variable group has value 2.

Thank you very much for your help.

Something like this?

\documentclass{article}

\begin{document}

\newcount\group
\newcount\subj
\newcount\nors

\group=0
\loop
\subj=0
{\loop
\nors=0
{\loop
{
group \the\group, subject \the\subj, run \the\nors
\par
\ifnum\group=2
\begin{figure}[h!]
\centering
\emph{includegraphics filenameone-\the\group-\the\subj-\the\nors}
\caption{Test of filenameone-\the\group-\the\subj-\the\nors}
\end{figure}
\par
\fi
}
\ifnum\nors<26
\repeat}
\ifnum\subj<2
\repeat}
\ifnum\group<2
\repeat

\end{document}


Sorry, I have always used a mixture of low-level \if commands and counter definitions, even if it is probably a bad practice.

I am not sure how \ifnum\value{group}=2 would work in your case but maybe that is all you need to wrap around your figure environment to get your original example working ...

• Indeed, adding \ifnum\value{group}=2 solved my problem. Thanks a lot!!!! – Miguel Mendes May 19 '16 at 15:15

If you don't mind an additional package, pgffor is quite handy to provide foreach-loops.

\documentclass{article}
\usepackage{graphicx}
\usepackage{pgffor}

\begin{document}

test

\foreach \n in {1,...,2}{
\ifnum\n=2%
\includegraphics{pic}%
\fi%
}

\end{document}