By the rules of TeX syntax, the "name" of a macro that starts with a \
(backslash) character must either
- consist of a single non-alphabetical character. Some examples:
\,
(insert thin space), \%
( the %
character), \\
(insert line break), \[
(open display math), and \)
(close inline math).
or
- contain only uppercase and lowercase alphabetical characters:
a-z
and A-Z
. No numerals, and no other characters belonging to non-letter categories either. (Well, there are certain ways of assigning "letter-category" status to non-letter characters, but that's a topic for a different discussion.)
Therefore, \EJ471
is not a valid macro name.
However, you could define a somewhat more general macro:
\newcommand{\EJ}[1]{\includegraphics[scale=0.150]{EJ_#1.jpg}}
and use it as in \EJ{471}
to pass EJ_471.jpg
to the \includegraphics
command. If you needed to process further jpg files that start with EJ_
(and end in .jpg
, of course), you could simply keep invoking this macro with the appropriate arguments.