Analyze bar graphs

[ralph001]

Hello,

I was wondering if there is anyway for me to be able to analyze graphs (i.e. bar graphs, line graphs, etc.) with imagej?  I am performing a meta analysis on some data, however I will be needing to extract information from others graphs as I do not have access to the raw data.  For example, I have a paper with a bar graph showing plant biomass in the presence and absence of spiders.  I need to be able to extract the data within the bar graph to get the mean, std deviation and sample sizes.  I will include an image of the graph to illustrate my point.

[Christophe CHAMOT-2]

Hi,

There are probably fully automated methods, but as an first approch, you
can just draw a line on the scale bar and hit "m" for measuring. Now you
know 189 pixels stands for 70 g/plot, just measure the other values by
drawing and hit "m" once. You will have a result table you can export in
EXCEL for the conversion ...

Hope it helps,

Christophe

Le 07/06/2010 13:04, ralph001 a écrit :

> Hello,
>
> I was wondering if there is anyway for me to be able to analyze graphs (i.e.
> bar graphs, line graphs, etc.) with imagej?  I am performing a meta analysis
> on some data, however I will be needing to extract information from others
> graphs as I do not have access to the raw data.  For example, I have a paper
> with a bar graph showing plant biomass in the presence and absence of
> spiders.  I need to be able to extract the data within the bar graph to get
> the mean, std deviation and sample sizes.  I will include an image of the
> graph to illustrate my point.
> http://imagej.588099.n2.nabble.com/file/n5148519/bar_graph.jpg
>    

--
Christophe CHAMOT
Responsable Technique PLATIM
IFR128 BioSciences Lyon-Gerland
04.72.72.87.62
www.ifr128.prd.fr/PLATIM