BEGIN{
	Stem="tmp";
	IGNORECASE=1;
	Comments="%.*";
	FS=",";
}

{ sub(Comments,"") }

/^[ \t]*$/          { next }

/@relation/         { Relation=$0 }

/@data/             { _data=1 } 

/@attribute/        { Attr[++A]=$0 }

/@relation/,/@data/ { next }

_data { 
	Rows++;
	Cols=NF;
	for(Col=1;Col<=Cols;Col++) D[Rows,Col]=$Col;
	next;
} 

END {  
	print Relation > OutputFile;
	
	for(I=1;I<=Cols-2;I++)
	{
		target="-"I"-";
		if (index(SelectedAttributes,target)!=0)
			print Attr[I] >> OutputFile;
	}
	print Attr[Cols-1] >> OutputFile;
	print Attr[Cols] >> OutputFile;

	print "@data" >> OutputFile;

	for(row=1;row<=Rows;row++)
	{
		sep="";
		for(I=1;I<=Cols-2;I++)
		{
			target="-"I"-";
			if (index(SelectedAttributes,target)!=0)
			{
				printf sep D[row,I] >> OutputFile;
				sep=",";
			}
		}
		#in case these are the only two selected, the seperator is set to "," in the middle
		printf sep D[row,Cols-1] >> OutputFile;
		sep=","
		printf sep D[row,Cols] >> OutputFile;
		print "" >> OutputFile; 
	}
}