This subroutine renders a chart for the "current" chart spec using the associated dataset specs and returns the full pathname of a (png) file containing the rendered chart.
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This subroutine renders a chart for the "current" chart spec using the associated dataset(s) and returns the full pathname of a (png) file containing the rendered chart.
The <chart_pathname> is a required parameter. The value passed may be blank or it may optionally specify the file name or the full pathname of the chart that is to be rendered.