ME 4990: Intro to CS�Object-Oriented Programming & Machine Learning 101

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String Op, Functions

Outline

• String, AD Chapter 8
• Basic Operations
• File Reading!!!

String

• String operation is never easier than python
• https://www.w3schools.com/python/python_strings.asp

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String: AD chapter 8

• String is a list in term of indexing
• Again, in python, index starts at 0

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String: length

• A sequence is a list
• Length of list can be found by:

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Traversal of string

• Use for loop

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String slicing

• Again, string is like a list in term of indexing

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You cannot change a string element

• String is not a simple list, it is immutable

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String methods

• Python is great for these methods
• https://www.w3schools.com/python/python_ref_string.asp

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• find() and index()
• count()
• split()
• Convert to float and int

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find() and index() method

• Example code: find_method.py

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find() and index() method

• You can specify start and end position

Just a trick

• What will be the output?

count()

• Find how many times a string repeats

split(): see split_method.py

Convert to float or int

• https://www.jquery-az.com/convert-a-python-string-to-int-and-float-by-using-int-and-float-class/

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Convert to float or int

• https://www.jquery-az.com/convert-a-python-string-to-int-and-float-by-using-int-and-float-class/

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Table file reading

Table file reading

• Example: file_reading.py

Special characters

• Special characters: