Command: log
  
Syntax: 
  x2 = log(x1)
  
Description: 
  Return the natural logarithm of x1.
  
Comments: 
  This function may be applied to an atom or to all elements
  of a sequence. Note that log is only defined for positive
  numbers. Your program will abort with a message if you
  try to take the log of a negative number or zero.
  
Example: 
     a = log(100)
       -- a is 4.60517
 
See Also: 
  sin, cos, tan, sqrt
  
