General ⇒ Setting figure counter using \ref

[greengrass]

Is it possible to obtain the figure number from its \ref?

For example. In chapter

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\ref{chap2}

I have a figure

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\ref{chap2_fig5}

which ends up being "Figure 2.5" in my document.

In a different chapter, I would like to have a figure, with the figure number corresponding to

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\ref{chap2_fig5}

i.e. I want it to also appear as "Figure 2.5".
I have done

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\setcounter{chapter}{\ref{chap2}}

but cannot figure out how to go about setting the figure counter.
Would it be something similar to

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\setcounter{figure}{\ref{chap2_fig5}} 

Any help would be greatly appreciated!!

[Stefan Kottwitz]

Hi,

I wouldn't repeat a figure and also the caption of the figure. Imagine you would to it several times, the order of the numbers wouldn't be ascending any more. I would refer to the figure in the other chapter instead of repeating, or, if the figure was changed, use a new number.

Though a straightforward solution would be to create a new counter (\newcounter), give it the value of the figure counter in chapter two and use the value of this new counter later.

Stefan

[greengrass]

Thanks for your input. I'm not quite sure how to go about using \newcounter in my case.

I actually don't need (or want) the order of the numbers to be sequential or ascending. All I want is for them to match (exactly) with previously defined figures. For example, it this special chapter, I want to be able to set the counter for chapter and figure (for each figure) so that the resulting figures may appear as "Figure 2.5", "Figure 2.8", "Figure 2.13". As mentioned, I can get the "2" by setting the chapter counter. I am just unsure of what to put in for the figure counter to get the 5, 8 and 13 in this example. Am I right that the value of \ref{chap2_fig5} is actually 2.5 and not just 5? if so, is there a command that would extract just the "5"?

[Stefan Kottwitz]

Could you use a different way than to manipulate counters? What's the point exactly? If needed in text or captions you could use \ref{chap2_fig5}, also in captions, just don't use the counter in the caption, use \ref{chap2_fig5} instead.

Stefan

[greengrass]

Its for the caption. I'm puzzled - are you saying that I could set the figure caption within the \caption?
I currently have:

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\begin{figure}[htp]
\centering
\subfloat
{\includegraphics[width=.9\linewidth]{pic1}} \\
\subfloat
{\includegraphics[width=.9\linewidth]{pic2}} 
\caption[]{figure caption here}
\label{fig: blah}
\end{figure}

It will appear as "Figure X.X figure caption here". Isn't the first bit "Figure X.X" controlled by the chapter and figure counter, and can only be changed by changing the counters?

[Stefan Kottwitz]

Here's a quick demonstration using the caption package:

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\usepackage{caption}
...
\begin{figure}[htp]
\centering
\subfloat
{\includegraphics[width=.9\linewidth]{pic1}} \\
\subfloat
{\includegraphics[width=.9\linewidth]{pic2}}
\caption*{\figurename~\ref{fig: blah}: figure caption here}
\end{figure}

See also the caption documentation.

Stefan

[greengrass]

Thank you so much!! That works and is so much better!!

[greengrass]

While using the following works beautifully

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\caption*{\figurename~\ref{fig: blah}: figure caption here}

I realised that it does not allow a label to be stored. Is there any way to have both the self defined figure number as well as a label so that I could reference it with \pageref?

I tried the following

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\caption[]{\figurename~\ref{fig: blah}: figure caption here}\label{fig_label}

and while this enables \pageref{fig_label}, the resulting figure caption turns out to be "Figure X.X: Figure 2.5: figure caption here", where the 2.5 came from \ref{fig: blah} and the X.X is from the current chapter and figure counter. Is there a neat way to get rid of "Figure X.X: "?