Understanding Type Casting in Python: A Comprehensive Guide
Types and casting in Python
Typecasting allows Python programmers to convert an entity from one data type to another. For instance, you may want to convert a string data type such as “2000” to a number type. But why do you need type casting in Python?”
You may want to take advantage of certain properties of a particular object data type. For instance, you may declare a string variable data type that has the operations of “+ and *) as we have learned earlier in our previous section on strings. But you may want to apply number operations such as “/, - and |.” For you achieve numerical operations on such a data type, you have to convert it, or typecast such a variable, to a number.
To cast between the different data types, you must specify the data type name as the function. There are several built-in functions that can help you to convert from one data type to another. Examples of these functions are:
|
Syntax |
Description |
|
int(x [base]) |
It converts the value x to an integer where the base defined is a string or not |
|
long(x [base] ) |
It converts the value x to the long integer where the base specified is x a string or not |
|
float(x) |
It converts the value xto floating point number |
|
complex (real [imag]) |
It produces a complex number |
|
str(x) |
It converts the object x to string data type |
|
eval(str) |
It evaluates the string and returns the object |
|
tuple(x) |
It converts the value xto a tuple |
|
list(x) |
It converts the value x to a list |
|
set(x) |
It converts the value xto a set |
|
dict(x) |
It converts the value x to a dictionary where x must be a sequence of the (key, value) tuples |
|
chr(x) |
It converts the integer to a character |
|
unichr(x) |
It converts an integer to the Unicode character |
|
ord(x) |
It converts the single character to its integer value |
|
hex(x) |
It converts an integer to a hexadecimal string |
|
oct(x) |
It converts an integer to an octal string |
Have a look at the example of the code below. What do you think will be the output?
x = "5000"
y = "2000"
print(x + y)
print( int(x) + int(y) )Output
50002000
7000Can you explain why the output is like that? Well, the first statement (print x+y) will display a concatenation of two strings: 5000 and 2000. In the second statement, the x variable has been converted to integer data type. Similarly, the second variable has also been converted to integer data type. Thus, the statement print (x+y) prints the sum of x and y, which is 7000.