“First, define positive(), a function that takes a sequence as an argument and counts up and returns how many positive numbers (numbers greater than 0) are in that sequence. You will want to notice that not only can you test equality using ==, you can also test for inequality using < (less than) and > (greater than).”

“Having done that, start with positive() and modify it to create pluses(). This function should compute and return the sum of all positive numbers—ignoring any numbers in the sequence that are negative or zero.”

#counting elements in a list

def positive(sequence):
    result = []
    for element in sequence:
        result = len(listing)
    return result

listing = [1, 2, 3]

positive(listing)

3

listing2 = [3, 5, 19, 65, 9]

positive(listing2)

3

listing2

[3, 5, 19, 65, 9]

len(listing2)

5

listing = [4, 5, 19, 2, 99]

positive(listing)

5

def positive(sequence):
    result = []
    for element in sequence:
        result = len(listing)
    return result > 0 

listing = [4, 5, 19, 2, -99]

positive(listing)

True

listing = [9, 16, 0, 94, -1] #listing all numbers that are positive (>0)

for element in (listing):
    if element > 0:
        print(element)

9
16
94

#sum of all numbers from a listing:

sum(listing)

118

def positive(sequence):
    result = []
    for element in (listing):
            if element > 0:
                print(element)

listing = [4, 5, 19, 2, -99]

positive(listing)

4
5
19
2