In Python, input and output are distinguished by the presence or absence of prompts (>>>). Lines that do not begin with a prompt are output from the interpreter. Note that a secondary prompt on a line by itself in an example means you must type a blank line; this is used to end a multi-line command

Type the following text to the right of the Python prompt and press the Enter key:

Here print evaluates each expression in turn and writes the resulting value to standard output (in the screen). If you would like to print a blank line, use print "\n"

>>>print "Hello welcome to python programming"

In python a hash (#) is used to denote comment, which will be skipped by the interpreter. For mutliline comment, each line should be started with a hash

>>>#this is a comment

Now lets start with variables. Try x=5 in the IDLE

>>>x=5 >>>x 5

Here, we have created a variable called 'x' and associated it with the value 5. Note that in Python there is no need to declare the variable or its type before using them. Everything is a object here!!! Also it is possible to convert type of variables.

Variable can only contain ascii characters, digits and underscores (no spaces or other symbols) also its should not start with a digit or cannot be any words from a list of reserved keywords of Python.

Try the following

>>>k=52.3E-4 >>>n=complex (3,4) >>>n.real >>>n.imag

Based on the data type of a variable, the interpreter allocates memory and decides what can be stored in the reserved memory. Therefore, by assigning different data types to variables, you can store integers, decimals, or characters in these variables.

Here we have used a simple assignment operator,('=') Assigns values from right side operands to left side operand. For example, c = a + b will assign value of a + b into c.

Numeric Types in Python

You can use ALT+P to repeat the last command in python IDLE