# Interactive Mode

Python has an interactive mode. You can type Python code and see the
results immediately. To start Python, open a unix shell and type
"python".
`
> python
Python 2.3.3 (#1, Jan 29 2004, 22:55:13)
[GCC 3.3.3 [FreeBSD] 20031106] on freebsd5
Type "help", "copyright", "credits" or "license" for more information.
>>>
`

At the `>>>` prompt you can enter Python code.
## Using Python as a calculator

`
>>> `**2+3**
5
>>> **4+6*8**
52
>>> **abs(-4)**
4
>>> **help(abs)**
Help on built-in function abs:
abs(...)
abs(number) -> number
Return the absolute value of the argument.
>>> 89**34
1902217732808760980190430983601716818363305103120555045416541165041L
>>> print 89**34
1902217732808760980190430983601716818363305103120555045416541165041
>>> "What... is the air-speed velocity of an unladen swallow?"
'What... is the air-speed velocity of an unladen swallow?'
>>> print "What do you mean? An African or European swallow?"
What do you mean? An African or European swallow?
>>>

## Importing a module

Python organizes functions into modules. There are a lot of built-in
modules and even more "third-party" modules (also
called *packages*).
`
>>> `**import math**
>>> **help(math)**
Help on module math:
NAME
math
FILE
/usr/local/lib/python2.3/lib-dynload/math.so
DESCRIPTION
This module is always available. It provides access to the
mathematical functions defined by the C standard.
FUNCTIONS
acos(...)
acos(x)
Return the arc cosine (measured in radians) of x.
asin(...)
asin(x)
Return the arc sine (measured in radians) of x.
[... rest of the output removed ...]
>>> **math.pi**
3.1415926535897931
>>> **math.sin(math.pi/2.0)**
1.0
>>>

## Print the Time of Day

`
>>> `**import datetime**
>>> **now = datetime.datetime.now()**
>>> **now**
datetime.datetime(2004, 2, 2, 19, 23, 28, 809434)
>>> **print now**
2004-02-02 19:23:28.809434
>>> **print "Now is", now.strftime("%d-%m-%Y"), "at", now.strftime("%H:%M")**
Now is 02-02-2004 at 19:23
>>>

The notation `name1.name2` is called an attribute lookup. In
this case, `name2` is an attribute of `name1` and has
some value.
`
>>> `**now.day**
2
>>> **now.year**
2004
>>> **now.hour**
19
>>>

This page based on
Some Simple Scripts.

Andrew Dalke
Last modified: Tue Feb 3 11:37:43 SAST 2004