Python examples: Difference between revisions

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Line 7: Line 7:
Type
Type


  x=1
  >>>x=1


and then simply
and then simply


  x
  >>>x


and you'll see
and you'll see
Line 20: Line 20:
Type  
Type  


  x=1.01
  >>>x=1.01


and then after you type "x" you'll see
and then after you type "x" you'll see


  x
  >>>x
  1.01
  1.01


Line 30: Line 30:
Clearly you have a real-time calculator in hand, so try something more exciting.
Clearly you have a real-time calculator in hand, so try something more exciting.


  x=1.01
  >>>x=1.01
  y=1.0001
  >>>y=1.0001
  x/y
  x/y


Line 40: Line 40:
Modify that with
Modify that with


  z=x/y
  >>>z=x/y
  z
  >>>z


and you'll see the same result.  But now try
and you'll see the same result.  But now try


  int(z)
  >>>int(z)


and you'll see  
and you'll see  


  1
  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

Revision as of 06:52, 7 February 2013

This page contains examples and links to programs used for our Research Methods - Programming with Python short course.

Very simple Python

Start a Python interactive session using the "python" command to get a >>> prompt.

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