MIA, Ask an Expert: abs xcor ycor and heading

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from: David Burke <burkd1@xxxxxxxxx>
date: Tue Nov 20 03:35:08 2007
platform: Mac OS10
version: MicroWorlds Ex

I have a game where my students have to navigate a polygon 
maze to win.  I want to check if there turtle is within a 
specified distance of the target.  I want their xcor, ycor 
and heading to be within 0.25, or any other chosen 
precision.  I was trying to get the ABS command to work for 
this with no luck.  Here is what I was trying:

ifelse abs 150 - xcor < 0.25 [pr [yes]] [pr [no]]

and more detailed:

ifelse and abs 150 - xcor < 0.25 abs 200 - ycor < 0.25 heading = 0 [pr [yes]] 
[pr [no]]
 
I use both PC and Mac