You can link the zoom behavior of multiple dygraphs by specifying a group when creating the graph. For example, the following code links the three graphs below. Try zooming one chart (done by mouse-selection) and note that the zoom range of the other graphs is also updated.

dygraph(ldeaths, main = "All", group = "lung-deaths")
dygraph(mdeaths, main = "Male", group = "lung-deaths")
dygraph(fdeaths, main = "Female", group = "lung-deaths")

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