Question

ON PYTHON:

''' Design the functions described below.
RECALL:
With functions that do not return a value and print a result to the console,
to test you must call the function, run it and visually inspect the result for correctness.
With functions that return a value, use the print_test function
to provide feedback of the test results at the command line.
The print_test function is implemented for you at the bottom of this file.
RECALL: floating point arithmetic can lose precision and therefore
we are restricting these functions to work on lists of integers or strings.
This allows us to compare 2 lists using ==.
ie. [1,2] == [1,2] or ['ab','cd'] == ['ab','cd']
'''

def main():
print('call your test functions from here')

'' Q5. Design a function that takes a list of tuples and
an additional integer specifying a position. The function
creates and returns a new list with the element from each tuple
at the specified position.
ie. if original list is [(1,2,3),(4,5,6)] and the specified position is 1
the returned list should be [2,5]
The function should not change the original list.
'''

''' Q6. Design a function that takes a list of tuples, a position (pos)
in the tuple and single value(v) that is the same type as the value
at the given position in the tuple. The function should create and
return a new list of only those tuples from the original list that
contain value v at position pos.
'''

# (str, bool -> None)
# prints test_name followed by 'passed' if expression evaluates to True,
# prints test_name followed by 'failed' if expression evaluates to False
def print_test(test_name, expression):
if(expression):
print(test_name + ': passed')
else:
print(test_name + ': failed')

# The following code will call your main function
if __name__ == '__main__':
main()

Answer 1

Here is the completed code for this problem. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

Note: Please maintain proper code spacing (indentation), just copy the code part and paste it in your compiler/IDE directly, no modifications required.

#code

''' Design the functions described below.
RECALL:
With functions that do not return a value and print a result to the console,
to test you must call the function, run it and visually inspect the result for correctness.
With functions that return a value, use the print_test function
to provide feedback of the test results at the command line.
The print_test function is implemented for you at the bottom of this file.
RECALL: floating point arithmetic can lose precision and therefore
we are restricting these functions to work on lists of integers or strings.
This allows us to compare 2 lists using ==.
ie. [1,2] == [1,2] or ['ab','cd'] == ['ab','cd']
'''

''' Q5. Design a function that takes a list of tuples and
an additional integer specifying a position. The function
creates and returns a new list with the element from each tuple
at the specified position.
ie. if original list is [(1,2,3),(4,5,6)] and the specified position is 1
the returned list should be [2,5]
The function should not change the original list.
'''


def function_Q5(tuples_list, position):
    #creating an empty list
    result = []
    #looping through each tuple in tuples_list
    for tup in tuples_list:
        #if position is a valid index on tup, appending element at position to result
        if position >= 0 and position < len(tup):
            result.append(tup[position])
        #otherwise if the position is invalid on this tuple, appending a None value
        else:
            result.append(None)
    #returning the result
    return result


''' Q6. Design a function that takes a list of tuples, a position (pos)
in the tuple and single value(v) that is the same type as the value
at the given position in the tuple. The function should create and
return a new list of only those tuples from the original list that
contain value v at position pos.
'''


def function_Q6(tuples_list, position, value):
    # creating an empty list
    result = []
    # looping through each tuple in tuples_list
    for tup in tuples_list:
        #checking if position is valid and tup contains value at position
        if position >= 0 and position < len(tup):
            if tup[position] == value:
                #adding current tuple to result list
                result.append(tup)
    return result


def main():
    # testing function_Q5()
    print_test('Q5 method test1', function_Q5([(1, 2, 3), (4, 5, 6)], 1) == [2, 5])
    print_test('Q5 method test2', function_Q5([(1, 2, 3), (4, 5, 6)], 0) == [1, 4])
    print_test('Q5 method test3', function_Q5([(1, 2), (3, 4), (5, 6)], 1) == [2, 4, 6])

    # testing function_Q6()
    # function_Q6([(1, 2, 3), (4, 5, 6)], 1, 2) returns [(1, 2, 3)] because only the first tuple
    # contain the value 2 at position 1
    print_test('\nQ6 method test1', function_Q6([(1, 2, 3), (4, 5, 6)], 1, 2) == [(1, 2, 3)])
    print_test('Q6 method test2', function_Q6([(1, 2, 3), (4, 5, 6)], 2, 6) == [(4, 5, 6)])
    print_test('Q6 method test3', function_Q6([(1, 2, 3), (4, 5, 6)], 2, 99) == [])


# (str, bool -> None)
# prints test_name followed by 'passed' if expression evaluates to True,
# prints test_name followed by 'failed' if expression evaluates to False
def print_test(test_name, expression):
    if (expression):
        print(test_name + ': passed')
    else:
        print(test_name + ': failed')


# The following code will call your main function
if __name__ == '__main__':
    main()

#output