latex: Undefined control sequnce [duplicate]

Question

Possible Duplicate:
Command for argmin or argmax?

For the following piece of LaTeX code,

{\hat \theta} 
    = { \argmin_{\theta \in \Theta}}

I got following error:

undefined control sequence={\argmin

How would I correct it?

Answer 1

That error means that the command \argmin is not known to Latex.

This is probably because Latex does not know this command. Unless you explicitly define the \argmin command in your document, or you use a package that defines it, it does not exist. To fix this problem, either define it (see here) or install a package that provides that command for you.