--- a/getting-started-with-lists/script.rst Wed Nov 17 23:24:57 2010 +0530
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,242 +0,0 @@
-.. Objectives
-.. ----------
-
-.. By the end of this tutorial, you will be able to
-
-.. Create Lists.
-.. Access List elements.
-.. Append elemets to list
-.. Delete list elemets
-
-.. 1. getting started with ipython
-
-
-
-.. Prerequisites
-.. -------------
-
-.. 1. getting started with strings
-.. #. getting started with lists
-.. #. basic datatypes
-
-.. Author : Amit
- Internal Reviewer : Anoop Jacob Thomas <anoop@fossee.in>
- External Reviewer :
- Language Reviewer : Bhanukiran
- Checklist OK? : <12-11-2010, Anand, OK> [2010-10-05]
-
-.. #[[Anoop: Slides contain only outline and summary
-
-Script
-------
- {{{ Show the slide containing title }}}
-
-Hello friends and welcome to the tutorial on getting started with
-lists.
-
- {{{ Show the slide containing the outline slide }}}
-
-In this tutorial we will be getting acquainted with a python data
-structure called lists. We will learn ::
-
- * How to create lists
- * Structure of lists
- * Access list elements
- * Append elements to lists
- * Delete elements from lists
-
-List is a compound data type, it can contain data of mutually
-different datatypes. List is also a sequence data type, all the
-elements are arranged in a given order.
-
-.. #[[Anoop: "all the elements are in order and **there** order has a
- meaning." - I guess something is wrong here, I am not able to
- follow this.]]
-
-We will first create an empty list with no elements. On your IPython
-shell type ::
-
- empty = []
- type(empty)
-
-
-This is an empty list without any elements.
-
-.. #[[Anoop: the document has to be continous, without any
- subheadings, removing * Filled lists]]
-
-Lets now see how to define a non-empty list. We do it as,::
-
- nonempty = ['spam', 'eggs', 100, 1.234]
-
-Thus the simplest way of creating a list is typing out a sequence
-of comma-separated values (or items) between two square brackets.
-
-As we can see lists can contain different kinds of data. In the
-previous example 'spam' and 'eggs' are strings whereas 100 and 1.234 are
-integer and float respectively. Thus we can put elements of different types in
-lists including lists itself. This property makes lists heterogeneous
-data structures.
-
-.. #[[Anoop: the sentence "Thus list themselves can be one of the
- element types possible in lists" is not clear, rephrase it.]]
-
-Example ::
-
- listinlist=[[4,2,3,4],'and', 1, 2, 3, 4]
-
-We access an element of a list using its corresponding index. Index of
-the first element of a list is 0. So for the list nonempty, nonempty[0]
-gives the first element, nonempty[1] the second element and so on and
-nonempty[3] the last element. ::
-
- nonempty[0]
- nonempty[1]
- nonempty[3]
-
-Following is an exercise that you must do.
-
-%% %% What happens when you do nonempty[-1].
-
-Please, pause the video here. Do the exercise and then continue.
-
-.. #[[Anoop: was negative indices introduced earlier, if not may be we
- can ask them to try out nonempty[-1] and see what happens and then
- tell that it gives the last element in the list.]]
-
-As you can see you get the last element which is 1.234.
-
-
-In python negative indices are used to access elements from the end::
-
- nonempty[-1]
- nonempty[-2]
- nonempty[-4]
-
--1 gives the last element which is the 4th element , -2 second to last
-and -4 gives the fourth from the last which, in this case, is the first element.
-
-We can append elements to the end of a list using the method append. ::
-
- nonempty.append('onemore')
- nonempty
- nonempty.append(6)
- nonempty
-
-Following are exercises that you must do.
-
-%% %% What is the syntax to get the element 'and'
-in the list,listinlist ?
-
-
-%% %% How would you get 'and' using negative indices?
-
-Please, pause the video here. Do the exercise and then continue.
-
-The solution is on your screen
-
-
-As we can see nonempty is appended with 'onemore' and 6 at the end.
-
-Using len function we can check the number of elements in the list
-nonempty. In this case it is 6 ::
-
- len(nonempty)
-
-
-
-Just like we can append elements to a list we can also remove them.
-There are two ways of doing it. One is by using index. ::
-
- del(nonempty[1])
-
-
-
-deletes the element at index 1, i.e the second element of the
-list, 'eggs'. The other way is removing element by content. Lets say
-one wishes to delete 100 from nonempty list the syntax of the command
-would be
-
-.. #[[Anoop: let x = [1,2,1,3]
- now x.remove(x[2])
- still x is [2,1,3] so that is not the way to remove
- element by index, it removed first occurrence of 1(by
- content) and not based on index, so make necessary
- changes]]
-
-::
-
- nonempty.remove(100)
-
-but what if there were two 100's. To check that lets do a small
-experiment. ::
-
- nonempty.append('spam')
- nonempty
- nonempty.remove('spam')
- nonempty
-
-If we check now we will see that the first occurence 'spam' is removed
-and therefore `remove` removes the first occurence of the element in the sequence
-and leaves others untouched.
-
-One should remember this that while del removes by index number,
-`remove` removes on the basis of content being passed on. For instance
-if ::
-
- k = [1,2,1,3]
- del([k[2])
-
-gives us [1,2,3]. ::
-
- k.remove(x[2])
-
-will give us [2,1,3]. Since it deletes the first occurence of what is
-returned by x[2] which is 1.
-
-
-
-
-
-
-
-.. #[[Anoop: does it have two spams or two pythons?]]
-
-.. #[[Anoop: there are no exercises/solved problems in this script,
- add them]]
-
-Following are exercises that you must do.
-
-%% %% Remove the third element from the list, listinlist.
-
-%% %% Remove 'and' from the list, listinlist.
-
-Please, pause the video here. Do the exercise and then continue.
-
-
-
-{{{Slide for Summary }}}
-
-
-In this tutorial we came across a sequence data type called lists. ::
-
- * We learned how to create lists.
- * How to access lists.
- * Append elements to list.
- * Delete Element from list.
- * And Checking list length.
-
-
-
-{{{ show Sponsored by Fossee Slide }}}
-
-This tutorial was created as a part of FOSSEE project.
-
-I hope you found this tutorial useful.
-
-Thank You
-
-..
- * Author : Amit Sethi
- * First Reviewer :
- * Second Reviewer : Nishanth