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TeX/ifnum

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< TeX

Synopsis

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\ifnum <integer-1><R><integer-2> <tex-code-1> [\else <tex-code-2>] \fi

With values:

%A TeX primitive counter:
\newcount\countA%
\countA=5%

%A LaTeX counter:
\newcounter{counterB}%
\setcounter{counterB}{5}%

Lorem ipsum...
\makeatletter% c@<countername> can access the integer value of the counter. To use it, @ must be a letter
\ifnum\countA=\c@counterB\relax%
	Text tells you, that both counters are the same.\newpage
\else%
	No new page here. The counters are not the same.
\fi%
Lorem ipsum...

Description

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The \ifnum command denotes the start of an if-then-else control structure. The forms <integer-1> and <integer-2> must expand to integers while <R> must be one of the characters '=', '<', or '>'. If <integer-1><R><integer-2> expands to a true expression then <tex-code-1> is processed; otherwise it is ignored. If the \else section is included and <integer-1><R><integer-2> expands to a false expression, then <tex-code-2> is processed; otherwise it is ignored.