A string consists of characters inside 'single quotes' or "double quotes". It can be any length and can contain letters, numbers, symbols, and spaces!!
A string can be considered a "list of characters".
Slicing a string:
What a helpful diagram this is!
If you want the letters b and l:
print(favorite_fruit[0:2])
It works like a number line - from 0 to 2 inclusive. It doesn't include any numbers from 2.01 and up, so the only numbers inside this slice are b and l.
Open ended selections work like this:
print(favorite_fruit[:4]) #this will print everything from 0 up to 4
output: blue
print(favorite_fruit[4:]) #this will print everything from 4 to the end of the string
output: berry
Slicing with a function:
Printing the last character of a string using len():
You write the following code:
last_character = favorite_fruit[len(favorite_fruit)]
print(last_character)
And you get an error... why? It's because the length of the string is 8 characters, and with a zero index it's 9. There's no character in the 9 position. So what do you do?
last_character = favorite_fruit[len(favorite_fruit)-1]
print(last_character)
Output will be y (for the word blueberry)
You can also slice the last few characters like this:
length = len(favorite_fruit)
last_characters = favorite_fruit[length-4:]
print(last_characters)
Output will be erry (the last 4 characters from blueberry)
It took many iterations for this to work out. It's ok, I think I get it now:
First, define the function to accept 2 items.
def password_generator(first_name, last_name):
Then assign a variable to accept the thing that you want: the last 3 letters of the first name and last name using the slicing method we learned just above:
temp_password = first_name[len(first_name)-3:] + last_name[len(last_name)-3:]
Then return whatever password this generates:
return temp_password
Then call it to use on the first_name and last_name entered above:
temp_password = password_generator(first_name, last_name)
Using negative indices to slice
The exercise for negative indices:
Strings are immutable
"Immutable" means that it cannot change once created. "Mutable" data types can change, and "immutable cannot be changed.
Example of trying to fix a string but it won't work: (Change name from Bob to Rob)
Escape characters
Escape characters are ones that have some kind of special meaning in python. If you accidentally end a string before including everything you need to, you can use the backslash to include it again. Here is an example:
fruit = "My favorite fruit" is blueberry ""
This can happen accidentally sometimes, so you add a backslash to the parts you want included in the string:
fruit = "My favorite fruit\" is blueberry\""
Still need some practice on this one:
This didn't work the first time because I forgot to return the counter!
Two exercises with commentary:
