I'm a newbie. the machine shows the error: "datums are required for this dimension" when I measure the perpendicularity, parallelism.... of any 2 lines. can someone guide me how to measure them? thank you so much!
I may be jumping to conclusions, but it seems "newbie" is an overstatement. Without some sort of formal training or extensive reading you're in for a world of heartache.
But to answer the question, if you're dimensioning the perp./ parallelism using xact measure or geotolerancing then one of the features will need to be defined as the datum using the "DATDEF" command. If using legacy dimensioning the second feature picked is always the datum.
