[texhax] align, align*, nonumber and ??

[Edsko de Vries]

On Thu, Oct 02, 2008 at 10:28:19PM +0200, Christian H. Aastrup wrote:
> Hi there!
> 
> When I write
> 
> \begin{align}
> a&=b\nonumber
> \\
> &=c \nonumber
> \\
> &=d
> \end{align}
> 
> I only get at number in the last line. But I want to do this in align and 
> need a command that makes a number rather than suppress it
> 
> \begin{align*}
> a&=b
> \\
> &=c
> \\
> &=d \yesnumber
> \end{align*}
> 
> Does such a \yesnumber command exist?

I don't know of a predefined one, but in my thesis I use:

% sometimes it is useful to tag some equations in an align* block but not
% others; \newtag can be used for this purpose
\newcommand{\newtag}{\tag{\theequation}\addtocounter{equation}{1}}

Edsko