distance between points

[salman]

I draw point using WCS. No I align WCS to some object and draw another point exactly at the same location where first point is drawn. Now in a lisp program I get the coordinates of the two points apply distance command to them display the disatance using alert command, it is show to be 0, but in an if statement when i check that condition, it does not work. Can anyone explain why the if statement is not working although the distance displayed between the point ( using alert ) is shown to be 0.

the reference code is

( setq dis( distance p1 p2 ) )

( if ( = 0 dis )

( alert "pts are same" )
)

[Lee Mac]

When working in different UCS's use TRANS to convert all the points to the WCS, then perform your calculations.

[TimSpangler]

and when using reals / integers it is best to use (equal instead or (= .

It allow for some fuzz.....