{conditionals} is about macros like \if and \ifx that may execute other macros depending on whether certain conditions are true or not. Popular packages are {etoolbox} and {ifthen}.

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23
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1answer
849 views

Use of \relax after \ifnum … \fi construction

I'm reading Malcolm Clark's A Plain TeX Primer. On page 111 there's an exercise to define a macro that prints the current time. I've reproduced Clark's answer below: \newcount\minleft ...
2
votes
1answer
1k views

Boolean operators: can I use AND, OR in `\ifthenelse`? How?

Can I use AND, OR in \ifthenelse? How, can you show me examples and documents? This would make my life easier.
7
votes
1answer
245 views

Is a page modulo 4?

If I want to test whether a page is odd/even (i.e. modulo 2) then I can use the following: \ifthenelse{\isodd{\thepage}}{}{} What can I do if I want to test whether a page is modulo 4? A minimal ...
15
votes
4answers
582 views

How to compare numbers with decimal point and logical OR operation?

I'm reading five values from external CSV file as [\sone, \stwo, \sthree, \sfour, \sfive]. Sample values could be [55.3, 89.0, 33.5, 40, 0.10]. Question : How to compare number with decimal points. ...
8
votes
1answer
130 views

Compare the height of arguments

I'm trying to define a \newcommand with three arguments. I'd like to: compare the height of these arguments choose the largest height to create frames (with that height) around the arguments. ...
0
votes
2answers
858 views

How to number a conditional equation

I am writing the following syntax to get a conditional equation. But the equation is not numbered. How can I number it? \[ f(x) = \begin{cases} x+7 & \text{if $5< x$}; \\ x^2-3 & \text{if ...
6
votes
2answers
301 views

How to select conditional text?

I've three variable statements : Statement1 = You are Great Student. Statement2 = You are average Student. Statement3 = You Need improvement on list of topics mentioned below. In the report ...
6
votes
4answers
365 views

Is there a better way to check divisibility in LaTeX?

I want to draw a trimmed ruler, for example, from 2.3cm to 3.9cm where the distance between two consecutive marks is 1mm. I have difficulty to efficiently check whether or not the counter is a ...
9
votes
3answers
278 views

What is wrong with \ifnum#1=0.09\relax?

The following code does not compile with the following error message Missing = inserted for \ifnum \documentclass[pstricks,border=4pt]{standalone} \usepackage{multido} ...
2
votes
1answer
108 views

Conditional execution based on style existence (listings)

Is there a way in LaTeX (or e-TeX) to check if a style is defined using the listings package (inside a \lstnewenvironment definition)? I mean something like this: \lstdefinestyle{tmpdefaultstyle}{} ...
12
votes
1answer
927 views

If not DeclareOption

I have some documents using a same custom package. That "header" package loads by default the package fullpage. But I would like to write a new LaTeX document, using the same header, but without ...
2
votes
1answer
114 views

Conditional use of multicol

I'm using the multicol package to get two columns, but sometimes the contents is too wide in a particular column and I was wondering if there is a way to first make sure the contents will fit ...
11
votes
2answers
193 views

How to create a macro “environmentally-dependent”

Yesterday I was reading the etoolbox documentation where there are defined some new document commands such as: \Before<Begin/End>Environment{<envir>}{<code>} % ...
4
votes
1answer
101 views

PSTricks, conditional frame size

Consider the following code: \documentclass{article} \usepackage{pst-eucl} \usepackage{siunitx} % LaTeX 3 syntax \ExplSyntaxOn \cs_new_eq:NN \calc \fp_eval:n \ExplSyntaxOff % constants ...
1
vote
0answers
27 views

Name separators, if condition for same command [duplicate]

I am new to LaTeX, just a Beginner, Basically a perl developer, I have created a .tex file \begin{document} \cont{\iname{\isurname{Name1}\ifname{K. C. G.}}\iname{\isurname{Name11}\ifname{Y. ...
6
votes
2answers
135 views

Separators for author group (IF conditon)

I am new to LaTeX, just a beginner, basically a Perl developer. I have created a LaTeX file \begin{document} \cont{\iname{\isurname{Name1}\ifname{K. C. G.}}\iname{\isurname{Name11}\ifname{Y. ...
3
votes
1answer
119 views

header-footer configuring

Need to start page numbering from the n-th page (in this case 6); used ifthen and fancyhdr packages. So, no dotted lines since page 6 and page 5 is already numbered. \usepackage{ifthen} ...
5
votes
2answers
325 views

Putting Multiline Conditional Equations

I am trying to write two equation like, a=b when a>1 a=c when a=0 One obvious choice is putting all in a tabular construct, as, \begin{tabular}{ll} $a=b$ & \text{when $a\ge 1$}\\ ...
5
votes
1answer
150 views

Any way to set a variable externally?

I just posted a question and can now generate a conditional section in a text: how to make a conditional document feature But to extend and generalize the question, first how could I create a ...
6
votes
2answers
182 views

how to make a conditional document feature

I saw in another question about how to create a condition, of which the best practice recommended was \iftoggle. I want to create a macro that will allow the creation of a teacher's note, a section ...
3
votes
1answer
88 views

`\ifhtlatex` needed for running tex4ht with different code [duplicate]

It is much easier to write my texts in an editor with LaTeX, but often clients ask for a word file. tex4ht does a good job, it produces html from a tex-file, which can be easily used. But there are ...
1
vote
1answer
278 views

Tabu/Longtabu: Conditional Column Definition

I want to create a longtabu table with a conditional number of columns: In development mode, 5 columns should be visiable. In the final version, only the first and the last column should be visible. ...
15
votes
5answers
665 views

Test if the first character of a string is 'a'

Is there an easy way to make a macro returning a string (e.g. 'true') if the string input begins by some fixed character, say 'a' ? I can't figure how to combine the different packages to do this. ...
6
votes
2answers
157 views

Branching construct based on the (babel) language selected

I'd like to keep one of my presentations in German and English and have defined a corresponding boolean variable withifthen and a command to typeset either the German or the English text. Is there ...
4
votes
1answer
571 views

conditional content

I'm writing a document in LaTeX that I want to compile in two different versions, V1 and V2 (with two different formatting specifications). Sometimes I need to insert a bit of content into V1 that ...
5
votes
1answer
59 views

Change Sectional Skip Conditioned on Text Existing or not Before Sectional Division

I have a simple document layout with a main heading for the title, and the possibility of starting the first sectional unit (with a standard \section command) right after the title -- meaning, with no ...
7
votes
3answers
248 views

Defining tabular rows with macros using `\ifnum` leads to `Incomplete \ifnum`

I am trying to define tabular rows using a macro which shall perform an conditional definition of the tabular row according to a given parameter. Please consider the following MWE: ...
14
votes
5answers
281 views

A macro that conditionally disregards the need for one of its arguments

Let's suppose I want to write nested equations that contain a fair few nested parenthetical/delimiter characters, like (), [], {}, ||, and perhaps others. Suppose too that I think these things look ...
9
votes
2answers
107 views

How to expand \ifthenelse so that it can be used in \parshape?

How do I get the following MWE to work: \documentclass{article} \usepackage{xifthen} \usepackage{lipsum} \newboolean{bar} \setboolean{bar}{true} \def\foo{\parshape = 2 ...
5
votes
1answer
65 views

How to “count” some table cells and print the result?

Thanks to an answer from David Carlisle found on this site I managed to code this: \documentclass[a4paper,10pt]{article} \usepackage{colortbl} \usepackage{xcolor} ...
4
votes
3answers
887 views

Misplaced \omit and \multicolumn in \IfEqCase

I have the following code with a command that creates rows for a tabular: \documentclass[letterpaper,10pt]{article} \usepackage[utf8]{inputenc} \usepackage{xstring} \newcommand*{\condrow}[2]{ ...
22
votes
2answers
447 views

Show footnotes on odd pages only

I'm writing my thesis using the scrbook-class. Is it possible to display footnotes only on the odd (right) pages? This should mean that \footnote{something} should be collected on even pages and ...
5
votes
1answer
825 views

Use of the comment package

In a .tex document, I'm using the comment package to produce two different versions (let's say : versionA and versionB) of the document. Each version contains different parts (it could be paragraphs, ...
17
votes
3answers
852 views

Conditionally Remove Brackets

I'm trying to create a command with an optional argument using \newcommand{\Af}[1]{{\mathbf{A}_{(#1)}} where the argument is a number. However, I'd like that if no argument is given the bracket ...
3
votes
1answer
197 views

Are there more to applications of \iftrue and \iffalse?

While reading "TeX for the impatient" on the topics of iftrue and iffalse, I encountered this example, \def\isbigger{\let\bigger=\iftrue} \def\isnotbigger{\let\bigger=\iffalse} \def\test#1#2{\ifnum ...
10
votes
1answer
465 views

XeTeX UNICODE Table

I would like to try to write a minimal XeTeX source that generates a comprehensive UNICODE table, substituting in local fonts as required by the current plane. I made the attached code as an MWE for ...
4
votes
1answer
97 views

Testing for “emptiness” (theoretical consideration)

Consider the following theoretical problem: Sometimes, in LaTeX one wants to do the simple test if a macro is empty, e.g. \def\foo{% This is... \ifx\baz\@empty Sparta! \else a pony farm. \fi } ...
13
votes
1answer
424 views

Create Two PDF versions of Classroom slides from Single LaTeX file: Teacher and Student

Is there a way to create a single document that will process a LaTeX file in two different ways (different preambles) and produce two different outputs. Specifically, I want to produce a set of ...
35
votes
3answers
5k views

Difference between \if and \ifx

I try to understand the subtleties of TeX programming, but it is not always easy. For example, in the following code : \def\first{abc} \def\second{abc} \ifx\first\second OK!\else false \fi I ...
6
votes
1answer
98 views

Conditionals in lstlistings

I am trying to put in some lines of code using the lstlistings-package but the code differs on conditionals. How can I only change some lines depending on the conditional? Assume I have the If: ...
9
votes
1answer
482 views

Conditional format for correlation table

I'm using the script by Christian Feuersänger: \documentclass{standalone} \usepackage{colortbl} \usepackage{pgfplots} \usepackage{pgfplotstable} \pgfplotstableset{ /color cells/min/.initial=0, ...
2
votes
2answers
115 views

How to make an 'if' on roman numbered pages and another 'if' on arabic numbered pages

I want to make some conditions on roman pages and another condition on arabic numbered page. (I want to know how to remove the background from specific pages in both numbering categories). ...
2
votes
0answers
195 views

Knitr/LaTeX: conditional execution based on external parameters

I'm using knitr to create LaTeX documents with integrated R code. Now I'd like to readout some external parameters (saved in a TXT or CSV file) and create a document based on the conditions specified ...
8
votes
2answers
264 views

Problem of having \begin…\end inside \ifdefined…\fi clause

I am using beamer, and have a LaTeX code as below. \ifdefined\VAR \begin{itemize} \item blahblab \end{itemize} \fi this does not compile, throwing an error: ! Incomplete \ifx; all text was ...
2
votes
1answer
72 views

Conditional based on packageoption

I added a counter to the todonotes packages \todo so I could display the total number of todos I have left. However I also enjoy working with the package option disabled. Therefore I would like to ...
5
votes
1answer
100 views

\IfFileExists is acting inconsistently when testing another boolean in conjunction with \input

I've been refactoring some code and clearing out obsolete commands. I don't understand what's happening here: \begin{filecontents}{mkif} \newif\ifaeRoughDraft \def\testforRoughDraft ...
13
votes
4answers
336 views

How do you test whether a known key value has been set in pgfkeys

Using the .code handler to my keys and a private macro, I can easily test whether a key has been set when using pgfkeys. For example: \documentclass{article} \newcounter{mytestenvcounter} ...
2
votes
0answers
108 views

Equivalent of CSS adjacent selector in LaTeX [closed]

In CSS you can use the adjacent selector to create conditional formatting. For example, p + p to format a paragraph that follows a paragraph, or h1 + p to format a paragraph that follows a h1 element. ...
4
votes
1answer
333 views

Replace lstlisting with verbatim depending on a boolean

I use latex2rtf to convert latex documents to .rtf and thence to MS-word (see this thread). To do this, I set up a custom class and limit which packages are used as latex2rtf only accepts a limited ...
10
votes
2answers
175 views

How to test if-condition using \csname within an \ifcase branch

I am trying to test an if-condition, where the name of the condition depends on a macro argument. To do this, I use \csname ifcondition#1 \endcsname. This works fine in a simple macro like this: ...