I write a document with LyX, to which I add PSTricks pictures in ERT sections.
I defined a
\newcommand in a certain ERT section, and it was available during this ERT section, but not available in the next ERT section.
I don't want to define this command in the preamble, because it is specific to a chapter.
How can I define a
\newcommand that will be available in all ERT sections of a given chapter?