{tex-core} is for questions that are independent of formats and macro packages. Such questions usually relate to low-level TeX programming or the behaviour of TeX at an underlying level. Note that even Plain TeX is a format in itself; for questions about it, use {plain-tex}.

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9
votes
1answer
143 views

Question about exercise 7.5 in TeXbook

Consider this extract from TeXbook: EXERCISE 7.5 Experiment with TEX to see what \string does when it is followed by an active character like ~. (Active characters behave like control ...
55
votes
1answer
1k views

Can TeX generate “heap dumps” to analyze+optimize out-of-memory situations?

As package author of the memory-extensive package pgfplots, I have been asked to analyze some out-of-memory situation. I could identify the "culprit"; it was some call to \pdfmdfivesum in which it ...
7
votes
1answer
56 views

What's the most plain way to define a parametrized macro within an outer macro definition

I often want to pass some arguments into a macro definition that defines an inner macro with parameters. For example \def\outmac #1,#2.{% \def\argone{#1} \def\argtwo{#2} \def\inmac #1,#2.{...
29
votes
1answer
777 views

What does “expanding” mean in (La)TeX?

You can often read about expanding a macro or when a macro does expand, sometimes about expansion. But what does this mean - in English?
4
votes
1answer
154 views

In LaTeX, what is the most efficient way to search for an optional token in given input?

My question is inspired by this comment by Joseph Wright. Let's say we have input strings with varying character combinations, such as: ...
1
vote
1answer
49 views

Writer2Latex table border removal

I'm using Writer2Latex to convert my .odt file, created in Google Docs and downloaded as .odt format, to .tex. It works but because there is no way to create columns of text in Google Docs other than ...
2
votes
1answer
230 views

Alignment in an enumerate environment using “\hspace” and “\hphantom” commands

I give a display of the first three problems from a multiple-choice test in algebra. The choices in the first problem are displayed using a tabbing environment, and the choices in the second and third ...
4
votes
0answers
122 views

Which algorithms does (La)TeX use? [closed]

People often talk about the many "typesetting wonders" (La)TeX can do because of the countless algorithms it uses. But exactly what are these typesetting algorithms? Concrete examples I have gathered ...
4
votes
1answer
82 views

Declaring array of integers

Is it possible to declare in TeX array of integer numbers ? What I am trying to do is to declare new tabular environment for very long tables spanning accross multiple columns and (or) pages. My ...
1
vote
1answer
117 views

Comma as letter and semicolon as operator in math formulas

Inside document source2e.pdf there are the following two lines \DeclareMathSymbol{,}{\mathpunct}{letters}{"3B} \DeclareMathSymbol{;}{\mathpunct}{operators}{"3B} which treats these two punctuation ...
3
votes
2answers
89 views

Define command to act like \ifvar

I'm trying to manipulate multiple boolean variables which are simply named one, two, three, etc. and since I'm using them with a counter, I have defined some commands to take a numerical input and ...
5
votes
2answers
74 views

How to \show the code of the command \autoref? [duplicate]

Edit: I think this is a duplicate of How can I see the "implementation" of the \LaTeX command? . I wanted to see the code for the hyperref \autoref command, so created this simple document: ...
22
votes
1answer
2k views

formal syntax rules of \dimexpr \numexpr \glueexpr

After looking at various answers on the site and by looking at the documentation of e-tex, I am still wondering what is exactly allowed in the various types of expressions, i.e. \numexpr, \dimexpr and ...
7
votes
2answers
552 views

Is there a complete modern book which explains how a TeX parser works?

Hi I am reading 'The TEXbook' by Donald E. Knuth. But in my point of view is very didactic for people who want to learn TeX. Most of the pages contain exercises. But many things of how a TeX ...
5
votes
3answers
274 views

macro who argument is proxy of next page break or beginning of a new slide

QUESTION: How do I write macros that run a control sequence \C (for example print a figure on the page or slide, a) right after the next page break (or new slide), or b) right before the next page ...
11
votes
1answer
216 views

Detecting the end of line

Minimal working example: \documentclass{article} \usepackage{color} \newcommand{\mytextcolor}[2]{\textbf{1}\textcolor{#1}{#2}\textbf{2}} \begin{document} This is \mytextcolor{red}{red color} rest of ...
53
votes
4answers
12k views

How to check if a macro value is empty or will not create text with plain TeX conditionals?

I have a macro which holds some text value, e.g. \macro{some text}. If it is empty, I would like for nothing to appear in the document, but it has some content of any kind which would produce text ...
1
vote
1answer
45 views

Table changes distance to preceding line depending on rows

This seems to be such a simple issue, but I still have not found an answer to this question. I am using a non-float tabular environment. Depending on how many rows my table has, the distance to the ...
5
votes
1answer
167 views

Segmenting a Bezier curve into equal lengths in tikz/pgf

I'm trying to draw two curves and then create equal sized segments/arcs using pgf/tikz but for some reason the segments are not equally sized. I want to go on and fill each segment with a different ...
12
votes
4answers
455 views

Ratio arithmetic in plain TeX

I would like to calculate the ratio between two dimensions and produce a dimensionless quantity for use in further calculation in the process. I seem to be unable to do so. Specifically, I run into ...
2
votes
0answers
57 views

Where is screed.tex? [closed]

In TeX for the Impatient, Chapter 2, Page 9, it asks to try compiling screed.tex. Where is screed.tex and why did the author not explain what it is?
11
votes
3answers
280 views

Treating the contents of a TeX-style group ({\blah …}) as macro arguments

I am trying to make adjustments to a large document that uses TeX-style macros, like this: {\defun SomeFunctionName arg1 arg2} The \defun macro is defined as \newcommand{\defun}{\tt}. Can I ...
9
votes
3answers
812 views

Detecting \global, \long, \outer, \protected

Is there a way to detect whether or not the next assignment is going to be \global, \long, \outer, or \protected? That is, is it possible to write a command \detectmodifiers such that code like \def\...
43
votes
2answers
2k views

Can you explain how this code works?

I found this code somewhere on the TeX archives and have been puzzling over it for some time. Can anyone describe how it works? % Date: Thu, 7 Feb 91 12:20:50 -0500 %From: amgreene@ATHENA.MIT....
0
votes
0answers
65 views

How to go about learning to program in Tex? [duplicate]

I have been using Tex for a few years now and enjoyed the work of others (e.g., ctan packages, templates, styles). My question sees to practical code to learn from. What would be a good primer, or ...
3
votes
1answer
75 views

TeX expert needed: how to \setto(optimal)width?

there is a problem I have been trying to solve for a while but without success so far. As far as I know, TeX is very good at appropriately breaking text lines with respect to a fixed container width. ...
8
votes
1answer
93 views

Is it possible to adjust the “quantization” of allowable skip lengths?

In plain TeX and derivative formats, the concept of stretchable/shrinkable length, AKA a glue or a skip or a rubber length exists, in general defined as <dimen> plus <stretch-dimen> minus ...
8
votes
5answers
589 views

A more elegant version of the \ifnot macro

A TUGboat article of 15 years ago mentions an \ifnot macro by David Kastrup whose implementation is: \def\ifnot#1{#1\else \expandafter\expandafter\fi \iffalse\iftrue\fi} However, this macro ...
14
votes
2answers
283 views

How can own commands be aware of \global?

When I define a command that defines commands \def\makefoobar{ \def\foo{foo} \def\bar{bar} } and prefix it with \global { \global\makefoobar } it is treated like { \global\def\foo{foo} \...
11
votes
2answers
124 views

split off function for variable as separator

How/Possible to change this implementation of \xSplit so that the separator is a variable filled in at the time of definition (\edef somehow?) or at the actual use of the command?? %based on the ...
9
votes
1answer
546 views

How do counts differ from numexpr

To do basic arithmetic on numbers, one can utilize TeX counts, \newcount\c \c=2 \advance\c 3 \typeout{\the\c} LaTeX counters \newcounter{c} \setcounter{c}{2} \addtocounter{c}{3} \typeout{\thec} ...
1
vote
1answer
94 views

How could I write a Latex tag in source form in section name?

I tried to use \verb|| and \lstinline[language={[LaTeX]TeX}]{} and they failed. I just want to write a name of latex tags in section names for internal purposes. For example, I couldn't compile a ...
41
votes
5answers
6k views

Should I read Donald Knuth's The TeXbook?

I've been using LaTeX for about a year or two as part of writing reports in university and want to gain a more in-depth understanding of how it works (I'm a computer science student). Would Donald ...
8
votes
3answers
309 views

Questions on macro writing in TeX to modify an existing style file: fancybox.sty

I've decided that I must become more adept at TeX if I'm to become proficient with LaTeX. While this is probably obvious to most readers who pass by, my ability to muddle through has hidden this small ...
13
votes
1answer
169 views

Inserting tokens at end of math mode

One can use \everymath and \everydisplay to insert tokens at the beginning of math mode, but what about inserting tokens at end of math mode? Lets say I want to enclose the math mode material in a ...
4
votes
2answers
244 views

Redefining line break (double backslash) for align environment

I am trying to figure out if it is possible to (locally) redefine \\ (double backslash) within amsmath's align environment. On the one hand, I'd like to be able to dynamically insert extra columns, on ...
38
votes
1answer
2k views

What do different \fontdimen<num> mean

I know that \fontdimen<num> returns some dimensions associated with the current font. What are they?
3
votes
1answer
86 views

How to avoid typesetting any cell if a table is empty

Following How can I define a macro that adds a row to a table that has not yet been printed?, I came up with a macro (\AddToTable) that “builds” a table, i.e. appends its argument as the last row of ...
25
votes
5answers
916 views

Most efficient way to reverse a token list (tail recursion)

Goal: reverse a list of characters, going from \def\mylist{abcdefgh} to \def\mylist{hgfedcba}. This is easy using a marker which does not appear in the list, such as \relax: \def\mylist{abcdefgh} \...
8
votes
3answers
141 views

Appending active and expansion sensitive characters to a macro

This question comes up pretty often when people want to build tables with empty columns or similarly building up some active characters inside a macro hoping to expand them at the right time right ...
26
votes
4answers
2k views

Display hyphenation options for a specific word

When TeX produces Overfull box, is puts something like this in the log: Overfull \hbox (15.47195pt too wide) in paragraph at lines 7--9 []\OT1/cmr/m/n/10 I re-ally re-ally want to get dis-played the ...
5
votes
2answers
2k views

how do you put caption on figures in sweave

I have this sweave code. I need to add caption to the figures. I am doing this but it looks like I see the figure before the section{Data ANALYSIS}: \documentclass[letter,12pt]{article} \...
19
votes
2answers
529 views

\expandafter and \aftergroup: where do the 2n+1 and n^2-1 rules come from?

Both TeX primitives \expandafter and \aftergroup have "rules of thumb" stating that \expandafter should be used 2n+1 times to look n tokens ahead (is this correct?). A similar "rule of thumb" holds ...
15
votes
3answers
809 views

How could the macro xii.tex be simplified into a better readable form

I was reading some TeX guides from where I have found this source: \let~\catcode~`76~`A13~`F1~`j00~`P2jdefA71F~`7113jdefPALLF PA''FwPA;;FPAZZFLaLPA//71F71iPAHHFLPAzzFenPASSFthP;A$$FevP A@@...
68
votes
3answers
110k views

Escape character in LaTeX

I need to output the below text but since \ is a special character, I cannot: [RegularExpression(@"\d+")] Also sometimes I need use dollar sign $ as well but it seems to be a special char, too. ...
1
vote
0answers
341 views

Memory overload due to pgfplots / tikz

first of all, I need to mention that there are 2 related threads, that I found usefull: 1, 2. I am working with TeXstudio 2.8.8 on Win 7 64bit (i5 @3.3GHz, 8GB RAM - if this matters). My goal is to ...
1
vote
1answer
279 views

Passing values from PythonTeX to LaTeX

I have read in the PythonTeX manual about how to pass LaTeX values to PythonTeX, but I cannot find any documentation (or a way) to do the reverse. For example, in the LaTeX package datenumber, one ...
3
votes
1answer
83 views

Specifying coordinates with \def in PSTricks

I'm starting with PSTricks. I use the following macro to set cartesian coordinates: \def\newPoint#1(#2,#3) { \expandafter\def\csname x#1\endcsname{#2} \expandafter\def\csname y#1\endcsname{#3}...
20
votes
1answer
402 views

How do I get into XeTeX development?

The support for OpenType fonts has been a great advancement in terms of usability. Unfortunately the microtype package does not offer font expansion for OpenType fonts in XeTeX. I dug a little ...
14
votes
3answers
959 views

How to get the catcode of a token?

For debugging a complicated macro I would like to print out the catcode of a token. Optimally I would like to have a macro \getcatcode such that, for example, \getcatcode{a} would expand to 10. How ...