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Python

Posted by Scott Halford
Scott Halford
8,964 Points

Slicing With A Step

Having trouble with an example in the video 'Slicing With A Step.'

When I do: my_list = list(range(20))

my_list[7-1] I get 6 not [7, 6, 5, 4]

It should be: my_list[7-1]

[7, 6, 5, 4, 3, 2]

1 Answer

Seth Kroger
Seth Kroger
56,416 Points
Seth Kroger
Seth Kroger
56,416 Points

The start of the slice and the step should be separated by colons, 2 since you don't have an end to the slice. Without them, you're asking for the index of 7-1 which is 6.

my_list[7::-1]

#or more generally
some_list[start:end:step]
Scott Halford
Scott Halford
8,964 Points

Thank you Seth for the explanation.