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IGB allows you to manipulate graph tracks in multiple ways, both by transforming an individual track or by combining two graph tracks in a mathematical way. Controls for transforming and combining graphs can be found in the Graph Adjuster tab tab. Any track that has been transformed or combined can be saved as .wig or .egr WIG, BEDGRAPH, or EGR (see File Formats for more details).
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You may want to duplicate a graph to experiment with different graph adjustments without losing adjustments that you have already made. The first choice in the Transform Track Operations *drop down menu is *Copy (see image of Graph Adjuster tab tab), which makes a copy of the graph without any transformation. This can be useful if you want to explore the effects of showing one graph in two graph styles at the same time.
Select the graph, set Transform Track Operations *to *Copy and click GO.
Transforming
By default, all graphs display in linear scale, but IGB allows you the option to transform a graph into other scales. Select the graph(s) and open the Graph Adjuster tab. Select the type of transformation you would like to perform from the pull-down menu labeled Transform, then click GOTrack Operations. The picture below includes all of the options available in IGB. However, many new Plug-ins add more transformation options which then populate this drop down list (see Plug-ins). Notice that for the Log function, there is an entry box Base: where you can set the base for log transformations.
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It is possible to join two or more graphs into a single track. The two (or more) graphs will then have a single track tier label and can be moved and adjusted as a group. To join multiple graphs, select them, then press the Join button in the Graph Adjuster panel Operations panel of the Graph tab. To separate these graphs, select the joined track and press the Split button.
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IGB allows you to work with 2 graph tracks at a time. The first track selected will be given a temporary label of 'A'. Shift click selection of the second track will give it the temporary label 'B'. After the two tracks have been selected, you choose the mathematical function from the Operations box. Multi-Graph option of the Operations panel.
The functions are: 
IGB will open an new track for the newly created graph. It will be titled as the name of the function performed, and then each of the original tracks in parenthesis. The new track can be adjusted for style and display just as any other graph track.
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