# What are the default values in LaTeX commands or variables

How can I know what is the default value for line spacing in LaTeX (for example what is the default value of \baselinestretch command before renewcommanding it?) and how I can print this value in the PDF file?

I used \the\textheight‎‎ to show the default value of text height in the output file.

I just tested these two commands in this simple example (in a report class and the font size is default):

\documentclass{‎‏‎report‎}‎‎‎

\begin{document}
\the\textheight‎‎
\end{document}


and I get 550.0pt in output.

Is there something like this to know and print all default values of all pre-defined variables in a LaTeX output? (in a report class with a default font size for instance)

• Since some of the commands using registers internally, the representation for printing/showing them differs. As far as I know there is no single command from Tex-core (or LaTeX - core) that shows all of them (that would be quite a lot) in a row. You should use the \let - approach in order to store the old definition in order to be able to restore it later on – user31729 Apr 23 '17 at 10:51
• The \baselinestretch macro expands to 1 for example (by default from LaTeX core). (Looking into latex.ltx provides some clue). Classes and packages might change this value, of course – user31729 Apr 23 '17 at 10:53
• – egreg Apr 23 '17 at 10:54
• Please consider, that packages and classes add new 'variables' that influence layout/font settings etc. – user31729 Apr 23 '17 at 11:01

LaTeX allocates

• 56 \count registers
• 92 \dimen registers
• 31 \skip registers
• 16 \box registers
• 4 \toks registers

Running a document with the report class allocates another

• 9 \count registers
• 1 \dimen register
• 2 \skip registers

Several of these parameters are for internal usage. If we exclude parameters with @ in their name, we get

### \count registers

\interfootnotelinepenalty
\interdisplaylinepenalty


### \dimen registers

\maxdimen
\normallineskiplimit
\jot
\leftmargin
\rightmargin
\listparindent
\itemindent
\labelwidth
\labelsep
\linewidth
\leftmargini
\leftmarginii
\leftmarginiii
\leftmarginiv
\leftmarginv
\leftmarginvi
\fboxrule
\fboxsep
\tabbingsep
\arraycolsep
\tabcolsep
\arrayrulewidth
\doublerulesep
\unitlength
\footnotesep
\topmargin
\oddsidemargin
\evensidemargin
\footskip
\textheight
\textwidth
\columnwidth
\columnsep
\columnseprule
\marginparwidth
\marginparsep
\marginparpush
\paperheight
\paperwidth


### \skip registers

\hideskip
\normalbaselineskip
\normallineskip
\smallskipamount
\medskipamount
\bigskipamount
\fill
\topsep
\partopsep
\itemsep
\parsep
\floatsep
\textfloatsep
\intextsep
\dblfloatsep
\dbltextfloatsep


The report class adds

• \bibindent (a \dimen)
• \abovecaptionskip (a \skip)
• \belowcaptionskip (a \skip)

There are also all the internal parameters of TeX that will have a default value (see List of TeX internal parameters? for a partial list, but you should consult the big manuals, either the TeXbook or TeX by topic).

All these (with the exception of box registers) can be looked at with \the.

There are also “pseudovariables”, that is, parameterless macros which hold a value. Among them

\baselinestretch
\arraystretch


and some more. These can be looked at with \meaning.

• Wow, thanks! It's a very nice answer, and I solved my problem with the help of your answer. I used \the\baselineskip‎ to show this \skip register in the output and (for my simple example in the question) I get 12.0pt. (In the case of my simple example, that was exactly what I wanted to know about \baselinestretch pseudovariable!) – Qaher Apr 24 '17 at 7:47