LyX ⇒ \DeclareMathOperator not working

[gandi]

I'm trying to define new math operators, using

Code: Select all

\DeclareMathOperator{\curl}{curl}

in the preamble, as described in the LyX Math Manual. This works fine in "normal" LaTeX, but in LyX I get an 'undefined control sequence' message when I try to convert to DVI or PDF.

Any ideas? Thanks!

[frabjous]

I don't know much about LyX, but in ordinary LaTeX, \DeclareMathOperator requires the amsmath pacakge. Is that being loaded in LyX?

[gandi]

Thanks, frabjous, a \usepackage{amsmath} in the preamble helped! Alternatively, I've just seen, in LyX one can also tick "Use AMS Math Package" in Document-->Settings-->Math Options.