Beginning Python - Chapter 1 Summary

IDLE is the Python "Integrated Development Environment".

On Windows, I ran it from "C:\Python26\Lib\idlelib\idle.bat".

Simple Python Examples:-

***Strings***

>>>print "hello, " + "world"

hello world

***Addition***

>>>2+2

4

***Division***

>>>10/3

3

***Power of***

>>>2 ** 3

8

***Variables***

>>>x = 3

>>>print x

3

***Get input***

>>>input("Please enter your age: ")

Please enter your age: 29

29

>>>raw_input("Please enter your name: ")

Please enter your name: Egon

Egon

***Functions***

>>>pow(3, 4)

81

>>> round (7.0/3.0)

2.0

***Modules***

>>> import math

>>> math.floor(32.9)

32.0

>>> from math import sqrt

>>> sqrt(9)

3.0

***Commenting***

>>># print "this is a comment"

>>> print "this is code"

this is code

***Representation***

>>> print (10000L)

10000

>>> print repr(10000L)

10000L

>>> temp = 42

>>> print "The temp. is " + `temp`

The temp. is 42

***Long Strings***

>>> print "hello, \

>>>world!

hello, world!

***Raw Strings***

>>> print "Hello \nWorld"

Hello

World

>>> print "c:\\program files\\python\\libs"

c:\program files\python\libs

***Saving & Executing Python Programs***

Create a new file called "test.py"

Edit with a text editor, and add the following:-

name = raw_input("What is your name? ")

print "Hello, " + name

name = raw_input("")

Save, and double click to run or from CMD - "python test.py".

FUNCTION	DESCRIPTION
abs(number)	Returns the absolute value of a number.
cmath.sqrt(number)	Returns the Square Root of a number.
float(object)	Converts a string or a number to a floating point number.
help()	Offers interactive help.
input(prompt)	Gets input from the user.
int(object)	Converts a string or number to an integer.
long(object)	Converts a string or number to a long integer.
math.ceil(number)	Returns the ceiling of a number as a float.
math.floor(number)	Returns the floor of a number as a float.
math.sqrt(number)	Square root, for non-negative numbers.
pow(x, y[, z])	x to the power of y (modulo z).
raw_input(prompt)	Gets input from the user, as a string.
repr(object)	Returns the string representation of a value.
round(number[, ndigits])	Rounds a number to a given precision.
str(object)	Converts a value to a string.