Lecture "Brute-force argorithms", exercise 4

[essepuntato]

Write in Python the function def my_range(stop_number), which behave like the built-in function range() introduced in Section "Insertion sort" and returns a proper list, and accompany the function with the related test case. It is not possible to use the built-in function range() in the implementation.

[ManuSrivastava1]

Here is my version of the range function -

def my_range(input):
    new_range = []
    x = 0
    while len(new_range)< input:
        new_range.append(x)
        x += 1
    return new_range

See the above-written code in action here

Here are the tests for my version of the range function -

def test_my_range(input,new_range,expected):
    i=0
    result = True
    while i<input:
        if new_range[i]==i:
            result = True
            i+= 1
        else:
            result = False
            break

    if expected==result:
        return True
    else:
        return False

test1 = test_my_range(4,[0,1,2,3],True)
test2 = test_my_range(4,[0,1,2,5],False)

See the above written code in action here

Note - In addition to the two above-mentioned tests, we can also write a test to check if our range function produces a list with the correct number of elements in it as the above-written test take that for granted and do not check that. Since my_range function has a relatively simple logic, I have choosen to not write that test here.

[RebeccaJillianBeattie]

[federicabonifazi]

[CarmenSantaniello]

def test_my_range(stop_number, expected):
    result = my_range(stop_number)
    if expected == result:
        return True
    else:
        return False

def my_range(stop_number):
    output_list = list()
    n = 0
    while n < stop_number:
        output_list.append(n)
        n += 1
    return output_list

print(test_my_range(3, [0, 1, 2])) 
print(my_range(3))

It returns:

True 
[0, 1, 2]

[olgagolgan]

[11051620]

def my_range(stop_number):
my_list = list()
i = 0

while i < stop_number:
    my_list.append(i)
    i += 1
    
return my_list

[martasoricetti]

[ManueleVeggi]

#Test code for the algorithm
def test_my_range(stop_number, expected_range):
    result = my_range(stop_number)
    if result == expected_range:
        return True
    else:
        return False

#Code for the algorithm
def my_range(stop_number):
    output_list = list()
    start_number = 0
    while stop_number > start_number:
        output_list.append(start_number)
        start_number = start_number + 1
    return output_list

#Test
print(test_my_range(3, [0, 1, 2])).      # N. 1, expect: T
print(test_my_range(3, [0, 1, 2, 3]))   # N. 2, expect: F
print(test_my_range(3, [1, 2, 3]))       # N. 3, expect: F
print(test_my_range(-3, [0, 1, 2]))     # N. 4, expect: F
print(test_my_range(3.1, [0, 1, 2]))    # N. 5, expect: F

If code is run, the results coincide with our expectations : therefore the code should be correct

[tommasobattisti]

def test_my_range(stop_number, expected):
    result = my_range(stop_number)
    if result == expected:
        return True
    else:
        return False
    
def my_range(stop_number):
    output_p_list3 = []
    while stop_number > 0:
        output_p_list3.append(stop_number -1)
        stop_number = stop_number -1
    return list(reversed(output_p_list3))

print(test_my_range(6, [0, 1, 2, 3, 4, 5]))   #True
print(test_my_range(0, []))   #True 

[katya-avem]

[OrsolaMBorrini]

def test_my_range(stop_number, expected):
    result = my_range(stop_number)
    if result == expected:
        return True
    else:
        return False

def my_range(stop_number):
    output_object = list()       # Create the the new list
    i = 0                        # Initialise the element we will add to the new list to 0
    while i<stop_number:         # When the condition is true we execute the following block
        output_object.append(i)  # We add the element to our new list
        i += 1                   # This instruction modifies the while-condition (sooner or later a<stop_number will be False)
    return output_object

print(my_range(2))
print(test_my_range(2,[0,1])) #True
print(test_my_range(2,[0]))   #False

[MaddaGh]

[AnastasiyaSopyryaeva]

Task_4

def testing(stop_number, expected):
    result = my_range(stop_number)
    if result == expected:
        return True
    else:
        return False

def my_range(stop_number):
    output = []
    start = 0
    while stop_number > start:
        output.append(start)
        start += 1
    return output


print(testing(3, [0, 1, 2]))
print(testing(-2, [0, 1]))
print(testing(5, [0, 1]))

Returns
True
False
False

[giorgimariachiara]

def test_my_range(stop_number, expected):
result = my_range(stop_number)
if expected == result:
return True
else:
return False

def my_range(stop_number):
output_list = list()
number = 0
while number < stop_number:
output_list.append(number)
number +=1
return output_list

print(my_range(6))
print(test_my_range(6, [0, 1, 2, 3, 4, 5]))