# Implementing nested if-then-else tests

I would like to implement the following processsing for each row of my data, which is read with datatool:

if ( (\No = 5 and \B=11111) OR (\No = 5 and \B=22222) ):
\inserpageA
else if ( (\No = 5) AND (\B not 11111) AND (\B not 22222) ):
\inserpageB
else:
\No \hspace{1cm} \B  \hspace{5cm} \A


My code:

\RequirePackage{filecontents}
\begin{filecontents*}{test.csv}
Acol, Bcol, NoCol
Ax,Bxxxx,1
Ay,By,3
A1,B22,2
A2,B44,4
A3,11111,5
Ax,B,1
Ay,By,3
A1,B22,2
A2,B44,4
A3,22222,5
Ax,Bxxxx,1
Ay,By,3
A1,B22,2
A2,B44,4
A3,33333,5
\end{filecontents*}

\documentclass{article}
\usepackage{datatool}
\newcommand{\inserpageA}[2]{%
\subsubsection*{AAA}
\newpage
}
\newcommand{\inserpageB}[2]{%
\subsubsection*{BBB}
\newpage
}
\begin{document}

\DTLforeach*{mydata}{\A=Acol, \B=Bcol, \No=NoCol}%
{%
\No \hspace{1cm} \B  \hspace{3cm}  \A

}%

\end{document}


Please show how to implement the above rule. Thank you.

There are several ways to do that. I propose two solutions, one using xifthen, the other using expl3. It would also be doable with ifthen and functions from datatool.

Note that for tests on \B, I used string comparison because the contents is not always a number, contrary to \No. I replaced one 2222 with 22222 in your logical expression (looks like a mistake in your question?).

I implemented the logical tests as you wrote them, but they could be simplified (the \No = 5 test could be factored out).

# Using xifthen

\RequirePackage{filecontents}
\begin{filecontents*}{test.csv}
Acol, Bcol, NoCol
Ax,Bxxxx,1
Ay,By,3
A1,B22,2
A2,B44,4
A3,11111,5
Ax,B,1
Ay,By,3
A1,B22,2
A2,B44,4
A3,22222,5
Ax,Bxxxx,1
Ay,By,3
A1,B22,2
A2,B44,4
A3,33333,5
\end{filecontents*}

\documentclass{article}
\usepackage{xifthen}
\usepackage{datatool}

\newcommand{\inserpageA}{%
\subsubsection*{AAA}
\newpage
}
\newcommand{\inserpageB}{%
\subsubsection*{BBB}
\newpage
}

\begin{document}

\DTLforeach*{mydata}{\A=Acol, \B=Bcol, \No=NoCol}%
{%
\ifthenelse{$$\cnttest{\No}{=}{5}\AND \equal{\B}{11111}$$\OR
$$\cnttest{\No}{=}{5}\AND \equal{\B}{22222}$$}%
{\inserpageA}%
{\ifthenelse{\cnttest{\No}{=}{5}\AND
\NOT\equal{\B}{11111}\AND
\NOT\equal{\B}{22222}}%
{\inserpageB}%
{\No\hspace{1cm}\B \hspace{5cm}\A\par}%
}%
}%

\end{document}


# Using expl3

Maybe you'll find the expl3 way more readable. Contrary to xifthen, boolean expressions for l3prg (the expl3 module for these things) use standard precedence rules for && and || (logical AND and logical OR, respectively), which is nice.

Note that spaces are ignored between \ExplSyntaxOn and \ExplSyntaxOff. If you need a space there, use ~ or \space. ~ may be ignored as usual after a control word, for instance the ~ in \B ~ is ignored, but \B \space will insert a space token when \space is expanded (it is a macro expanding to an explicit space token).

\RequirePackage{filecontents}
\begin{filecontents*}{test.csv}
Acol, Bcol, NoCol
Ax,Bxxxx,1
Ay,By,3
A1,B22,2
A2,B44,4
A3,11111,5
Ax,B,1
Ay,By,3
A1,B22,2
A2,B44,4
A3,22222,5
Ax,Bxxxx,1
Ay,By,3
A1,B22,2
A2,B44,4
A3,33333,5
\end{filecontents*}

\documentclass{article}
\usepackage{xparse}
\usepackage{datatool}

\ExplSyntaxOn

\NewDocumentCommand \lfortiProcessOneRow { }
{
\bool_if:nTF
{ % The parentheses below are not necessary, because && has higher
% priority than || in expl3 (l3prg) boolean expressions.
( \int_compare_p:nNn { \No } = { 5 } && \str_if_eq_p:Vn \B {11111} ) ||
( \int_compare_p:nNn { \No } = { 5 } && \str_if_eq_p:Vn \B {22222} )
}
{ \inserpageA }
{
\bool_if:nTF
{ \int_compare_p:nNn { \No } = { 5 } &&
! \str_if_eq_p:Vn \B {11111}       &&
! \str_if_eq_p:Vn \B {22222}
}
{ \inserpageB }
{ \No \hspace{1cm} \B \hspace{5cm} \A \par }
}
}

\ExplSyntaxOff

\newcommand{\inserpageA}{%
\subsubsection*{AAA}
\newpage
}
\newcommand{\inserpageB}{%
\subsubsection*{BBB}
\newpage
}

\begin{document}

\DTLforeach*{mydata}{\A=Acol, \B=Bcol, \No=NoCol}{\lfortiProcessOneRow}

\end{document}


# Output of both examples

• super. Thank so much. I tested add "\ifthenelse{(\cnttest{\No}{=}{1})}% {\inserpageA} before \ifthenelse{(\cnttest{\No}{=}{5}\AND \equal{\B}{11111})\OR (\cnttest{\No}{=}{5}\AND \equal{\B}{22222})}%" ..but don't work. How can i add more condition: If \No = 1, insert page A. Thanks – latexforti Aug 22 '19 at 7:46
• You are missing a braced group for the “else” part. Look at the xifthen manual page 2. The syntax is \ifthenelse{〈test expression〉}{〈true code〉}{〈false code〉}. Also, you don't need the parentheses here (( and )) but when you use them in an xifthen test, they must be preceded by a backslash, as in $$ or $$. – frougon Aug 22 '19 at 7:49
• I added an expl3-based solution, you may find it easier to work with. Look for Boolean expressions in interface3.pdf for documentation on l3prg (expl3) boolean expressions. – frougon Aug 22 '19 at 10:10