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+.. Objectives
+.. ----------
+
+.. #. How to print some value
+.. #. How to print using modifiers
+.. #. How to take input from user
+.. #. How to display a prompt to the user before taking the input
+
+.. Prerequisites
+.. -------------
+
+.. 1. Loops
+
+.. Author : Nishanth Amuluru
+ Internal Reviewer : Puneeth
+ External Reviewer :
+ Checklist OK? : <put date stamp here, if OK> [2010-10-05]
+
+Script
+------
+
+Hello friends and welcome to this tutorial on Input/Output
+
+{{{ Show the slide containing title }}}
+
+{{{ Show the slide containing the outline slide }}}
+
+Input and Output are used in almost every program we use.
+In this tutorial, we shall learn how to
+
+ * Output data
+ * Take input from the user
+
+type
+::
+
+ a = "This is a string"
+ a
+ print a
+
+<<<<<<< local
+print a, prints the value of a.
+=======
+``print a``, obviously, is printing the value of ``a``.
+>>>>>>> other
+As you can see, even when you type just a, the value of a is shown.
+But there is a difference.
+
+.. #[Amit: The next sentence does seem to be clear enough]
+
+Typing a shows the value of a while print a prints the string. This difference
+becomes more evident when we use strings with newlines in them.
+type
+::
+
+ b = "A line \n New line"
+ b
+ print b
+
+As you can see, just typing b shows that b contains a newline character.
+While typing print b prints the string and hence the newline.
+
+Moreover when we type just a, the value a is shown only in interactive mode and
+does not have any effect on the program while running it as a script.
+
+.. #[punch: I think we could show that?]
+
+We shall look at different ways of outputting the data.
+
+<<<<<<< local
+.. #[Amit: C's printf syntax ?? i think its better to elaborate the
+ idea]
+
+print statement in python supports string formatting.
+Various arguments can be passed to print using modifiers.
+=======
+``print`` statement also accepts the syntax of C's ``printf`` statement.
+Various arguments can be passed to ``print`` using modifiers.
+>>>>>>> other
+type
+::
+
+ x = 1.5
+ y = 2
+ z = "zed"
+ print "x is %2.1f y is %d z is %s"%(x,y)
+
+As you can see, the values of x and y are substituted in place of
+``%2.1f`` and ``%d``
+
+{{{ Pause here and try out the following exercises }}}
+
+%% 1 %% What happens when you do ``print "x is %d y is %f" %(x, y)``
+
+{{{ continue from paused state }}}
+
+We see that the ``int`` value of x and ``float`` value of y are
+printed corresponding to the modifiers used in the print statement.
+
+We can also see that ``print`` statement prints a new line character
+at the end of the line, everytime it is called. This can be suppressed
+by using a "," at the end ``print`` statement.
+
+Let us see this by typing out following code on an editor as print_example.py
+
+{{{ open an editor }}}
+type
+::
+
+ print "Hello"
+ print "World"
+
+ print "Hello",
+ print "World"
+
+Now we run the script using %run /home/fossee/print_example.py
+
+As we can see, the print statement when used with comma in the end, prints a
+space instead of a new line.
+
+Now we shall look at taking input from the user.
+We will use the ~~raw_input~~ for this.
+type
+::
+
+ ip = raw_input()
+
+The cursor is blinking indicating that it is waiting for input
+type
+::
+
+ an input
+
+and hit enter.
+Now let us see what is the value of ip by typing.
+::
+
+ ip
+
+We can see that it contains the string "an input"
+
+{{{ Pause here and try out the following exercises }}}
+
+%% 2 %% enter the number 5.6 as input and store it in a variable called c.
+
+{{{ continue from paused state }}}
+
+We have to use the raw_input command with variable c.
+type
+::
+
+ c = raw_input()
+ 5.6
+ c
+
+Now let us see the type of c.
+
+::
+
+ type(c)
+
+We see that c is a string. This implies that anything you enter as input, will
+be taken as a string no matter what you enter.
+
+{{{ Pause here and try out the following exercises }}}
+
+%% 3 %% What happens when you do not enter anything and hit enter
+
+{{{ continue from paused state }}}
+
+::
+
+ d = raw_input()
+ <RET>
+ d
+
+We see that when nothing is entered, an empty string is considered as input.
+
+raw_input also can display a prompt to assist the user.
+::
+
+ name = raw_input("Please enter your name: ")
+
+prints the string given as argument and then waits for the user input.
+
+{{{ Pause here and try out the following exercises }}}
+
+%% 4 %% How do you display a prompt and let the user enter input in next line
+
+{{{ continue from paused state }}}
+
+.. #[Puneeth: We didn't talk of new-line character till now, did we?]
+.. #[Puneeth: non-programmers might not know?]
+
+.. #[Amit: Well there is a discussion earlier about new lines, I think its good
+.. as a slight trick question. But may be next line is a more easier lexicon]
+
+The trick is to include a newline character at the end of the prompt string.
+::
+
+ ip = raw_input("Please enter a number in the next line\n> ")
+
+prints the newline character and hence the user enters input in the next line
+
+{{{ Show summary slide }}}
+
+This brings us to the end of the tutorial.
+In this totorial we have learnt
+
+ * How to print some value
+ * How to print using modifiers
+ * How to take input from user
+ * How to display a prompt to the user before taking the input
+
+{{{ Show the "sponsored by FOSSEE" slide }}}
+
+
+This tutorial was created as a part of FOSSEE project, NME ICT, MHRD India
+
+Hope you have enjoyed and found it useful.
+Thank You.
+