Presentation Graphics Error Codes
 If an error occurs during the execution of a presentation graphics
 procedure, the variable ChartErr will contain a non-zero value.
 For non-BASIC errors, the error numbers can be tested using numerics or
 constants as defined in the CHRTB.BI header file. The meaning of a non-BASIC
 error.

 Number    Constant name      Type of error

 15        cBadLogBase        LogBase <= 0
 20        cBadScaleFactor    ScaleFactor = 0
 25        cBadScreen         Invalid screen mode
 30        cBadStyle          Invalid chart style
 105       cBadDataWindow     Data window calculated
                                  too small
 110       cBadLegendWindow   Legend-window coordinates
                                  invalid
 135       cBadType           Invalid chart type
 155       cTooFewSeries      Too few series
                                  (first% > last%)1
 160       cTooSmallN         No data in series (n% = 0)2
 165       cBadPalette        Palette not dimensioned
                                  correctly
 170       cPalettesNotSet    SetPaletteDef procedure hasn't
                                  been used
 175       cNoFontSpace       No more room for new fonts


 Numbers greater than 100 are fatal errors and will cause charting routines
 to exit.
 If BASIC generates an error, the value of ChartErr is equal to 200 plus the
 BASIC error number. (See Appendix D, "Error Messages" for a complete list of
 BASIC error messages.)