Math & Science ⇒ Double Label in 'flalign' Environment

[yiorgosb]

I have been given a book which contains many code blocks like the below

Code: Select all

\begin{flalign*}
a_{11}& =b_{11}&
a_{12}& =b_{12}\\
a_{21}& =b_{21}&
a_{22}& =b_{22}+c_{22} \label{one} \label{two}
\end{flalign*}

containing more than one labels. This results to an error

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! Package amsmath Error: Multiple \label's: label 'one' will be lost.

I have no idea why they have used two labels to reference the same equation, but I have to figure out a way to "link" the second label to the first in order to avoid replacing every second label in all over the book.

Any suggestions?

[localghost]

These labels do not make any sense at all since the starred version of this environment won't display equation numbers. Even if you could make it work, commands for cross reverences would yield simply nothing.


Thorsten

[yiorgosb]

These labels do not make any sense at all since the starred version of this environment won't display equation numbers. Even if you could make it work, commands for cross reverences would yield simply nothing.


Thorsten

You are right about this.
But there are lots of non-star-version align-blocks also.
What about these?

[localghost]

This still makes no sense. Even it would work, you would get the same reference for both labels. I guess that the authors of this book just did a mistake with labelling the equations this way. A visual example of the original output could be very helpful to see what they had in mind when doing this.