From AIMSWiki

Numbers

The standard arithmetical operators on numbers are defined:

• Addition

>>> 2 + 3
5

• Subtraction

>>> 1000000000000000 - 1
999999999999999L

• Multiplication

>>> (3 + 2j) * 1j
(-2+3j)

• Division

>>> 1.0 / 8.0
0.125

from __future__ import division

• Exponentiation

>>> 400 ** 0.5
20.0

There are some unusual ones:

• Floor division (literally, dividing two numbers and taking the floor of the result)

>>> 3.5 // 0.6
5.0

• Remainder

>>> 3.5 % 0.6
0.50000000000000011

(Note the small error caused by using floating point numbers.)

Strings

Coming soon...

Lists

The following examples use the lists

x = ['a', 1, 'b', 2]
y = [3, ['hello', 'there'], 10.25]

Joining and repeating lists

>>> x + y
['a', 1, 'b', 2, 3, ['hello', 'there'], 10.25]
>>> x * 3
['a', 1, 'b', 2, 'a', 1, 'b', 2, 'a', 1, 'b', 2]

Adding to a list

>>> x += [9.5, 3.25]
>>> print x
['a', 1, 'b', 2, 9.5, 3.25]
>>> x.append(4)     # This adds a single element to the end of the list
>>> print x
['a', 1, 'b', 2, 9.5, 3.25, 4]

Comparing lists

>>> x == y
False
>>> y == [3, ['hello', 'there'], 10.25]
True

Finding and changing elements in a list

>>> 'b' in x    # Check if a value is in the list
True
>>> 3 in x
False

>>> del x[2]    # This deletes the value at index 2 from the list
>>> print x
['a', 1, 2, 9.5, 3.25, 4]

Logical operators

• Equal to: ==
• Not equal to: !=
• Less than: <
• Less than or equal to: <=
• Greater than: >
• Greater than or equal to: >=
• Logical and: and
• Logical or: or
• Logical not: not

Here is a pretty complex example:

(x >= 0) and (x <= 3) and not ((x > 1) and (x < 2))

If x has the value 0.5, the above evaluates to

( True ) and ( True ) and not ((False) and (True ))
( True ) and ( True ) and not (False)
( True ) and ( True ) and ( True )
True

On the other hand, if x is 1.1:

( True ) and ( True ) and not ((True ) and (True ))
( True ) and ( True ) and ( False )
False

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