# File: Exercise2_2.py (Chapter 2, Execise 2)
# Purpose: generate a series of bar charts that compare drug use thru time
# Author: Emily G. Allen

# Import pylab
from pylab import *

# Import drug data
from DrugData import *

def drugBar():
    
    hold(1) # hold the figure so all bar graphs plot

    # plot the bars
    bar(Year, Alcohol, color = 'k')
    bar(Year, Cigarettes, color = 'y')
    bar(Year, Marijuana, color = 'r')
    bar(Year, Cocaine, color ='g')

    # label the graph
    xlabel('Time')
    ylabel('Percentage of Students')
    title('Alcohol, Cigarettes, Marijuana, and Cocaine Use by Seniors over Time')

    show()   # show the figure