data type part 1
Importance of Data Type Conversion in Programming
Data often needs conversion to the appropriate type for calculations and manipulations.
Incorrect data types can lead to errors in code execution.
Example in Python: Rating Input
A variable is used to store a rating, expected to be a whole number.
When a floating-point number (e.g., 2.2) is entered, two main issues arise:
The decimal number is accepted instead of being rejected.
The output is displayed as the input value multiplied by 100 rather than performing the intended calculation.
Key Concepts in Troubleshooting
Troubleshooting Approach
Fix one problem at a time.
Addressing multiple problems simultaneously complicates issue identification if fixes do not work as intended.
Understanding Default Input Data Type
Inputs are stored as strings by default.
This can lead to incorrect calculations unless conversion happens.
Example: The line intended to multiply the rating by 100 outputs the rating as a repeated string instead.
Data Type Conversion
Convert the rating from string to integer using the
int()function for accurate calculations.Usage:
rating = int(rating)(to convert before calculations).
Functions and Methods in Python
Functions: Procedures that perform specific actions, such as data type conversion.
Examples of built-in functions:
int()for integers,str()for strings.You will also learn how to create custom functions.
Methods: Specialized functions tied to class instances, allowing access and modification of instance data.
Handling String and Integer Concatenation
After converting the rating correctly, a new error occurs when attempting to concatenate:
Error arises from combining integer with string, which Python does not implicitly convert.
To resolve this, convert the integer result back into a string before concatenation.