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Python math works like you would expect.

There is a built in exponentiation operator (two stars), which can take either integers, floating point or complex numbers. This occupies its proper place in the order of operations.

Dividing two integers or longs uses integer division, also known as “floor division” after division. So, for example, 5/2 is 2. ”/” does “true division” for floats and complex numbers; for example, 5.0/2.0 is 2.5.

Dividing by or into a floating point number (there are no fractional types in Python) will cause Python to use true division. To coerce an integer to become a float, 'float()' with the integer as a parameter

This can be generalized for other numeric types: int(), complex(), long(). Beware that rounding errors can cause unexpected results. For example:

The modulus (remainder of the division of the two operands, rather than the quotient) can be found using the % operator, or by the divmod builtin function. The divmod function returns a tuple containing the quotient and remainder.

Unlike some other languages, variables can be negated directly:

There is shorthand for assigning the output of an operation to one of the inputs:

>>> x = 2 >>> x # 2 2 >>> x *= 3 >>> x # 2 * 3 6 >>> x += 4 >>> x # 2 * 3 + 4 10 >>> x /= 5 >>> x # (2 * 3 + 4) / 5 2 >>> x **= 2 >>> x # ((2 * 3 + 4) / 5) ** 2 4 >>> x %= 3 >>> x # ((2 * 3 + 4) / 5) ** 2 % 3 1 >>> x = 'repeat this ' >>> x # repeat this repeat this >>> x *= 3 # fill with x repeated three times >>> x repeat this repeat this repeat this

or:

if a or b: do_this else: do_this

and:

if a and b: do_this else: do_this

not:

if not a: do_this else: do_this