Append Method in Python

Python Help
1

I know this is a simple code, but somehow I kind of wonder why it is so…

my_list = [ ]

for i in range (5):
my_list.append (i + 1)

print(my_list)

[1, 2, 3, 4, 5]

I was thinking of [2,3,4,5,6]. Because it is i+1 for each number from 1 to 5…
Thank you in advance for the explanation.

2

The range() function yields values which start from 0, not 1, by
default. This matches the use of indices, which also count from 0.

Try this:

 print(list(range(5)))

Cheers,
Cameron Simpson cs@cskk.id.au

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3

range(5) produces a sequence of 5 integers starting with 0, not 1

By providing the parameter 5 you’re saying: give me 5 numbers, starting from 0 and stopping when you get to 5.

To append the numbers 1 to 5 you’d do this:

my_list = []

for i in range(1, 6):
    my_list.append(i)

print(my_list)

This way the range gives you all the numbers from start to stop, but does not include stop. This is called a “half open range” in computing.

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4

Oh, starts from 0. I may have confused it again. Thank you for the reply!

6

Thank you for the reply. I get it now.

7

These are also equivalent:

# Convert an iterable to a list
my_list = list(range(1, 6))

# Use a list comprehension
my_list = [i for i in range(1, 6)]
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