+ Returns a random floating point number in the allowable range of turtle
+ coordinates along the x axis.
+
+ These range from min-pxcor - 0.5 (inclusive) to max-pxcor + 0.5 (exclusive)
+
+ See http://ccl.northwestern.edu/netlogo/docs/dictionary.html#random-cor"
+ (let
+ ((min (- (min-pxcor) 0.5d0))
+ (max (+ (max-pxcor) 0.5d0)))
+ (+ min (clnl-random:next-double (- max min)))))
+
+(defun random-ycor ()
+ "RANDOM-YCOR => RANDOM-NUMBER
+
+ARGUMENTS AND VALUES:
+
+ RANDOM-NUMBER: a float, the random result
+
+DESCRIPTION:
+
+ Returns a random floating point number in the allowable range of turtle
+ coordinates along the y axis.
+
+ These range from min-pycor - 0.5 (inclusive) to max-pycor + 0.5 (exclusive)
+
+ See http://ccl.northwestern.edu/netlogo/docs/dictionary.html#random-cor"
+ (let
+ ((min (- (min-pycor) 0.5d0))
+ (max (+ (max-pycor) 0.5d0)))
+ (+ min (clnl-random:next-double (- max min)))))
+
+(defun one-of (list-or-agentset)
+ "ONE-OF LIST-OR-AGENTSET => RESULT
+
+ LIST-OR-AGENTSET: LIST | AGENTSET
+ RESULT: RANDOM-VALUE | RANDOM-AGENT | :nobody
+
+ARGUMENTS AND VALUES:
+
+ LIST: A list
+ AGENTSET: An agent set
+ RANDOM-VALUE: a value in LIST
+ RANDOM-AGENT: an agent if AGENTSET is non empty
+
+DESCRIPTION:
+
+ From an AGENTSET, returns a RANDOM-AGENT. If the agentset is empty, returns :nobody.
+ From a list, returns a RANDOM-VALUE. If the list is empty, an error occurs.