By the way, I get around this presently by adding a bogus value, doing the process screening and then removing the bogus value afterwards.
dt << Add Rows( 1 );
rowz = N Rows( dt );
:LOT[rowz] = 1;
ps = dt << Process Screening(
Process Variables( Eval( SpecCols ) ),
Grouping( :WAFER, :LOT ),
Control Chart Type( "Indiv and MR" ),
Within Sigma( 0 ),
Overall Sigma( 0 ),
Stability Index( 0 ),
Mean( 0 ),
Show Tests( 0 ),
Test 1( 0 ),
Out of Spec Rate( 0 ),
Latest Out of Spec( 0 ),
Cpk( 0 ),
Ppk( 0 )
);
dt_result = Report( ps )[Outline Box( "Process Screening" ), Table Box( 1 )] <<
Make Into Data Table;
ps << close window;
dt << Delete Rows( rowz );
Slán
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