Setting axes limits with googleVis

I posted about the various googleVis axis options for base charts, such as line, bar and area charts earlier, but I somehow forgot to mention how to set the axes limits.

Unfortunately, there are no arguments such as ylim and xlim. Instead, the Google Charts axes options are set via hAxes and vAxes, with h and v indicating the horizontal and vertical axis. More precisely, I have to set viewWindowMode : 'explicit' and set the viewWindow to the desired min and max values. Additionally, I have to wrap all of this in [{}] brackets as those settings are sub-options of h/vAxes. There are also options minValue and maxValue, but they only allow you to extend the axes ranges.

Here is a minimal example, setting the y-axis limits from 0 to 10:




With more than one variable to plot I can use the series argument to decide which variables I want on the left and right axes and set the viewWindow accordingly. Again, here is a minimal example:

Session Info

sessionInfo()
R version 3.0.1 (2013-05-16)
Platform: x86_64-apple-darwin10.8.0 (64-bit)

locale:
[1] en_GB.UTF-8/en_GB.UTF-8/en_GB.UTF-8/C/en_GB.UTF-8/en_GB.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] googleVis_0.4.3

loaded via a namespace (and not attached):
[1] RJSONIO_1.0-3

How to set axis options in googleVis

Setting axis options in googleVis charts can be a bit tricky. Here I present two examples where I set several options to customise the layout of a line and combo chart with two axes.

The parameters have to be set in line with the Google Chart Tools API, which uses a JavaScript syntax. In googleVis chart options are set via a list in the options argument. Some of the list items can be a bit more complex, often wrapped in {} brackets, e.g. for various formatting options or in [] brackets, if there are multiple series to consider. Within those brackets sub-options are set via argument : value, using the : character for assignments.

There are many other options as part of the Google Chart Tools API, which are not supported by googleVis yet, such as columns roles, controls and dashboards, etc. Please get in touch if you have ideas in this regard and/or would like to collaborate.

In my first example I display two series of dummy data in a line chart with two axes. The left hand scale is in percentages and the right hand scale in amounts. Note in the code below how I set the various parameters and the placements of the different kinds of brackets.
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