Please note that all dimensions are given in points, which is a unit equal to 1/72 of an inch. The default chart region is 6” by 4.5” which fits nicely into most published material. This is equivalent to:

ch.New 0 0 432 324  © or just 
ch.New 432 324

as the default starting location is the lower left corner. To set the charting region to a different shape, or to restrict the chart to a partial area, use this function with (x1,y1,x2,y2) in points from the lower left corner.

It may be helpful to call this function to reset the chart area to a convenient co-ordinate range before you add bitmaps or metafiles as ‘artworks’ to your completed chart:

ch.New 1000 1000
ch.Bitmap 'logo' ¯10 ¯10

This will add your logo in the top right corner of the chart area.