author | Santosh G. Vattam <vattam.santosh@gmail.com> |
Wed, 16 Sep 2009 16:57:49 +0530 | |
changeset 65 | 0f25f22a2725 |
child 67 | 5076574b7b83 |
permissions | -rw-r--r-- |
65
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
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======= |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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Strings |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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======= |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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Strings were briefly introduced previously in the introduction document. In this |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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section strings will be presented in greater detail. All the standard operations |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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that can be performed on sequences such as indexing, slicing, multiplication, length |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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minimum and maximum can be performed on string variables as well. One thing to |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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be noted is that strings are immutable, which means that string variables are |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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unchangeable. Hence, all item and slice assignments on strings are illegal. |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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Let us look at a few example. |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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|
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0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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:: |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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>>> name = 'PythonFreak' |
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Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
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>>> print name[3] |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
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h |
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Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
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>>> print name[-1] |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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|
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k |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
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>>> print name[6:] |
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Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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Freak |
0f25f22a2725
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Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
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>>> name[6:0] = 'Maniac' |
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Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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|
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Traceback (most recent call last): |
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Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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|
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File "<stdin>", line 1, in <module> |
0f25f22a2725
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Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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|
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TypeError: 'str' object does not support item assignment |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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This is quite expected, since string objects are immutable as already mentioned. |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
changeset
|
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The error message is clear in mentioning that 'str' object does not support item |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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|
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assignment. |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
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0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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String Formatting |
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Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
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================= |
0f25f22a2725
Added the strings_dict.rst file.
Santosh G. Vattam <vattam.santosh@gmail.com>
parents:
diff
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