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This page contains examples and links to programs used for our Research Methods - Programming with Python short course.
Start a Python interactive session using the "python" command to get a >>> prompt.
There are many built-in features of Python that are described in the documentation, but to get started let's do something very easy.
Type
>>>x=1
and then simply
>>>x
and you'll see
1
Type
>>>x=1.01
and then after you type "x" you'll see
>>>x 1.01
Clearly you have a real-time calculator in hand, so try something more exciting.
>>>x=1.01 >>>y=1.0001 x/y
and you'll see something like this
1.0098990100989902
Modify that with
>>>z=x/y >>>z
and you'll see the same result. But now try
>>>int(z)
and you'll see
1
That is, the function int() took the integer part of z. You can put that in another variable such as
>>>a=int(z) >>>a 1
Curiously, a seems to be an integer. It is said to be dymanically typed in this assignment. That can change. If you now add a little bit to a you'll see it turns into a floating point number
>>>a = a + 0.001 >>>a 1.001
There's much more you can do, of course, but you need to import the math functions first. Here's one way to do that.
>>>import math
Now try
>>>math.pi
and you'll see
3.141592653589793
The functions in the math package need the "math." in front of them.
>>>math.sin(math.pi/4.)
returns
0.7071067811865475
as does
>>>math.sqrt(0.5)
Similarly
>>>4.*math.asin(math.sqrt(0.5))
returns
3.1415926535897936
The comprehensive list of math functions is on the Python documentation site. You can try out some of the more exotic possibilities on your own.