set line color# <style> <thickness>
Sets current line attributes. 
color#:    one of the 16 GrADS default colors or a new color defined with set rgb
style:     1 - solid 
          
           2 - long dash 
  
           3 - short dash 
  
           4 - long dash, short dash 
  
           5 - dotted 
  
           6 - dot dash 
  
           7 - dot dot dash 
  
thickness: values range from 1 to 6