Types in python
Boolean
Boolean values are represented by True and False. They are often
produced by comparison operations.
print(3 > 2) print(10/5 == 1)
True False
Note: Above I am using print to see the results of the
comparison, but if you're in IPython, you don't need to do this.
Integers
x = 1 print(x + 3)
4
Floats
x = 1.0 print(x + 3.0)
4.0
If you add an integer to a float, the result will be a float.
x = 1.0 print(x + 3)
4.0
Strings
These are characters and words. They must be surrounded by either single or double quotes.
name = 'john'
Strings have some convenient methods associated with them. For example:
print(name.upper()) print(name.capitalize())
JOHN John
Note: If you're in IPython, you can find out what methods are
available for an object (like the string name above) by typing the
object and a period and then hitting tab. So, in this case,
name.<TAB> will show you all the available methods for a str.
Lists
A list is a sequence of values.
primes = [2, 3, 5]
Each value can be accessed individually.
print(primes[0]) print(primes[2])
2 5
The index (the value inside the brackets) is 0-based.
Lists can also be iterated over one-by-one.
for prime in primes: print(prime)
2 3 5
Dictionaries
Dictionaries store key-value pairs.
prices = {'car' : 40000, 'pop' : 1} print(prices['pop'])
1