# Lab 7, CS0007, Fall 2009
#
# Files and 2-dimensional arrays
#
# Precondition for the input files in this module:
# The file must also have 3 header lines.
# After that, Each line of the 
# file contains the average monthly temperatures for a year (separated
# by spaces) starting with January.
#
# Make through you trace through your code so you understand the data
# structure, and how you are accessing its components!
#

# So you have practice with them, use nested lists to represent the temperatures.
# Each element of the list is a list of 12 measurements, one for each month.
#
# Then, e.g., temperatures[2][5] is the temperature in the 5th month of the second year.
#
# Let's use a smaller example:  suppose we have only 3 years and 4 months, and the data
# is the following:
#
#24.7    25.7    30.6    47.5   
#16.1    19.1    24.2    45.4   
#10.4    21.6    37.4    44.7
#
#
#  Your list will be:
#  [[24.7,25.7,30.6,47.5],[16.1,19.1,24.2,45.4],[10.4,21.6,37.4,44.7]]
#
#  We'll number the years 0 to 2, and the months 0 to 3.
#
#  temperature[2][3] is 44.7, the temperature for year 2, month 3.
#
#  This is like using 2-dimensional arrays in other languages,
#  an important thing to know.
#
#  There isn't really much code to write!  Some functions should
#  call other functions in the file, and each function can be written
# in a few lines.

def input_temperature_data(filename):
    '''Open the specified filename,
    read past the three-line header, read in the temperature data on
    the file, and close the file.  Return the temperature data in the
    form of a list of lists, where each list element is a list of 12
    temperature readings.'''

    # Hint: use readline to read the first three lines, and then
    # a while loop as in files.py to read the numbers
    #
    # Hint: you need to convert the strings read from input to float numbers
    pass
    

def avg_temp_march(temp_data):
    '''Return the average temperature for the month of March as a float 
    for all years in temp_data. temp_data is the data structure returned
    by input_temperature_data.'''

    pass


def avg_temp(temp_data, mo):
    '''Return the average temperature for month mo as a float for all
    years in temp_data, where mo is an integer
    between 0 and 11, representing January to December,
    respectively. temp_data is the data structure returned
    by input_temperature_data.'''

   pass


def higher_avg_temp(temp_data, mo1, mo2):
    '''Return either mo1 or mo2 (integers representing months in the
    range 0 to 11), whichever has the higher average temperature for
    all years in temp_data.  If the months have the 
    same average temperature, then return -1. temp_data is the data structure returned
    by input_temperature_data.'''

    pass

def avg_temps (temp_data):
    ''' Return the average of all the temperatures sotred in temp_data. temp_data is the
    data structure returned by input_temperature_data.'''

if __name__ == '__main__':

    temp_data = input_temperature_data("lab7.dat")
    print avg_temp_march(temp_data),"sb",32.475
    print avg_temp(temp_data,3),"sb",46.525
    print higher_avg_temp(temp_data,2,3),"sb",3