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Quick background: I'm using texniccentre on windows vista, Miktex 2.9 installed.

I'm trying to make use of the iopams.sty file in order to use the \fl command in equations.

My header is set to this:

\usepackage[Lenny]{fncychap} %makes nice chapter headings
\usepackage{url} %use urls in references, etc.
\usepackage{multirow} % for different no of rows per column
%make refs [1-9]

I get many undefined control sequences, it looks like each new command given in the iopams.sty file gives its own undefined control sequence (I apologise for not being able to give the output stream, texniccentre doesn't seem to want to let me copy and paste the output it gives).

Furthermore the \fl command itself is recognised as an undefined control sequence. This led me to wonder if \fl might be part of amsmath, so I took out iopams from my header, and it still gave \fl as an UCS. STrangely I can't seem to find the \fl command in either the amsmath.sty or iopams.sty files, yet I know for a fact it's in there as I've used it before and it's documented as part of iopams.

Does anyone have any experience using these bits in question? Thanks

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Welcome to TeX.SX! A tip: If you indent lines by 4 spaces, then they're marked as a code sample. You can also highlight the code and click the "code" button ({}). – Claudio Fiandrino Jul 18 '12 at 15:47

You can't use the sty on its own. At least the version (1997/02/13 v1.0) I found needs an accompaning class (e.g. iopart.cls). This class defines your command \newcommand{\fl}{\hspace*{-\mathindent}}.

I don't recommend the use of the class (it is very old).

Btw: Every latex run generate a log-file which contains the error messages.

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