author | Puneeth Chaganti <punchagan@gmail.com> |
Wed, 21 Apr 2010 15:12:08 +0530 | |
changeset 96 | 3498d74ed615 |
parent 95 | fddcfd83e4f0 |
child 97 | 25248b12f6e4 |
permissions | -rw-r--r-- |
96
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Changed outline of strings.org.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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* Strings |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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*** Outline |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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***** Strings |
3498d74ed615
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* basic manipulation |
3498d74ed615
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* operations |
3498d74ed615
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* immutability |
3498d74ed615
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* string methods |
3498d74ed615
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* split and join |
3498d74ed615
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* formatting - printf style |
3498d74ed615
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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***** Odds and Ends |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* dynamic typing |
3498d74ed615
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* comments |
3498d74ed615
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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***** Simple IO |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* raw_input |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* console output |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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***** Arsenal Required |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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******* lists |
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Puneeth Chaganti <punchagan@gmail.com>
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******* writing to files |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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*** Script |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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Welcome friends. |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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|
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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In this tutorial we shall look at data types available in Python and |
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Puneeth Chaganti <punchagan@gmail.com>
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how to perform simple Input and Output operations. |
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Puneeth Chaganti <punchagan@gmail.com>
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for 'Numbers' we have: int, float, complex datatypes |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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for Text content we have strings. |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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For conditional statements, 'Booleans'. |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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Now we shall look at Python Strings. |
fddcfd83e4f0
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Puneeth Chaganti <punchagan@gmail.com>
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In python anything enclosed inside quotes(single or double) is a string |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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so |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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a = 'This is a string' |
fddcfd83e4f0
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Puneeth Chaganti <punchagan@gmail.com>
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print a |
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Puneeth Chaganti <punchagan@gmail.com>
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b = "This too!" |
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Puneeth Chaganti <punchagan@gmail.com>
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print b |
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Puneeth Chaganti <punchagan@gmail.com>
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c = '''This one too!''' |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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print c |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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d = """And one more.""" |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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print d |
fddcfd83e4f0
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Puneeth Chaganti <punchagan@gmail.com>
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fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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Similar to lists we covered earlier even string elements can be accessed |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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via index numbers starting from 0 |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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|
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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print a[0] |
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Puneeth Chaganti <punchagan@gmail.com>
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print a[5] |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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will |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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To access last element we can use a[-1] which is one of Pythons feature. |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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print a[-1] |
fddcfd83e4f0
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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len function works with the strings also as it does with the arrays and |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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returns length of the string. |
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Puneeth Chaganti <punchagan@gmail.com>
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Puneeth Chaganti <punchagan@gmail.com>
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One thing to notice about the string variables is that they are |
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Puneeth Chaganti <punchagan@gmail.com>
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immutable, that is |
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Puneeth Chaganti <punchagan@gmail.com>
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a[0] = 't' |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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will throw an error |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
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Some of methods available for string are: |
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Puneeth Chaganti <punchagan@gmail.com>
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a.startswith('Thi') |
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Puneeth Chaganti <punchagan@gmail.com>
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returns true if initial of the string is same |
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Puneeth Chaganti <punchagan@gmail.com>
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similarly there is endswith |
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Puneeth Chaganti <punchagan@gmail.com>
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a.endswith('ING') |
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Puneeth Chaganti <punchagan@gmail.com>
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a.upper() returns a string with all letters capitalized. |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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and a.lower() returns a string with all smaller case letters. |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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As we have seen earlier use of split function, it returns the list after |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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splitting the string, so |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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a.split() |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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will give list with three elements. |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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we also have 'join' function, which does the opposite of what |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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split does. |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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''.join(['a','b','c']) will return a joined string of the list we pass |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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to it. Since join is performed on '' that is empty string we get 'abc' |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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if we do something like |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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'-'.join(['a','b','c']) |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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|
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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we come to the end of this tutorial on introduction of Data types in |
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Puneeth Chaganti <punchagan@gmail.com>
parents:
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75 |
Python. In this tutorial we have learnt what are supported data types, |
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Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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supported operations and performing simple IO operations in Python. |
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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77 |
|
fddcfd83e4f0
Split data-files.org into numbers and strings.
Puneeth Chaganti <punchagan@gmail.com>
parents:
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*** Notes |