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The problem is probably due to the value option gvis.plot.tag, which should be " NULL " by default. To get the value of this option, use the command getOption("gvis.plot.tag").
Here are two ways display the googleVis chart "outChart":
1: Set the option gvis.plot.tag to NULL by using the command options(gvis.plot.tag=NULL). Then, the command plot(outChart) will display the chart in a local browser instead of printing code.
2: Print the chart to a .html file and then display that file. For example, to print the chart to the file "outChart.html" in the current working directory, type print(outChart, file="outChart.html"). The command plot.gvis("outChart.html") will display the chart in a local browser.
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