CSVHandling.py

"""
Week 3 practice project template for Python Data Analysis
Reading and writing CSV files using lists
"""


import csv



#########################################################
# Part 1 - Week 3



def print_table(table):
    """
    Echo a nested listto the console
    """
    for row in table:
        print(row)


def read_csv_file(file_name):
    """
    Given a CSV file, read the data into a nested list
    Input: String corresponding to comma-separated  CSV file
    Output: Lists of lists consisting of the fields in the CSV file
    """
    table = []
    
    openfile = open(file_name, "rt",newline = '')
    reader = csv.reader(openfile)
    
    for row in reader:
        table.append(row)   
        
    return table



def write_csv_file(csv_table, file_name):
    """
    Input: Nested list csv_table and a string file_name
    Action: Write fields in csv_table into a comma-separated CSV file with the name file_name
    """
    
    openfile = open(file_name, "w", newline='')
    writer = csv.writer(openfile, delimiter=' ')
    
    for item in csv_table:
        writer.writerow(item)
        
    openfile.close()
    
    

        
def test_part1_code():
    """
    Run examples that test the functions for part 1
    """
    # Simple test for reader
    test_table = read_csv_file("test_case.csv")  # create a small CSV for this test
    print_table(test_table)
    print()
    # Test the writer
    cancer_risk_table = read_csv_file("cancer_risk05_v4_county.csv")
    write_csv_file(cancer_risk_table, "cancer_risk05_v4_county_copy.csv")
    cancer_risk_copy = read_csv_file("cancer_risk05_v4_county_copy.csv")
    
    # Test whether two tables are the same
           
    for row in range(len(cancer_risk_table)):
        for col in range(len(cancer_risk_table[0])):
            if cancer_risk_table[row][col] != cancer_risk_copy[row][col]:
                print("Difference at", row, col, cancer_risk_table[row][col], cancer_risk_copy[row][col])
    
test_part1_code()