What are data type conversion functions?

Type conversion function are built in Python functions which are used to convert values from one type to an other. The built-in type conversion functions are:

Function	Function description
int(x [,base])	Converts an argument (x) to an integer. The base is specified if x is a string.
float(x)	The float function converts x to a floating point number.
long(x, [,base])	The long function converts argument x to a long integer Base specifies the base if and argument is a string.
complex(real [,imag])	Creates a complex number
str(x)	Converts argument \(x\) to string.
repr(x)	Converts object x to an expression strng.
eval(x)	The function evaluates a string and returns an object.
tuple(x)	Converts argument \(x\) to a tuple.
set(x)	Converts argument \(x\) to a set.
dict(x)	Converts argument \(x\) to dictionary.
frozenset(x)	Converts x to a frozen set (makes them immutable).
chr(x)	Converts an argument x (integer) to a character.
unichr(x)	Converts an integer (argument x) to a Unicode character.
ord(x)	Converts a single character to its integer value.
hex(x)	Converts integer to a hexidecimal string.
oct(x)	Converts an integer to an octal string.

Example 1 Convert string values to integer values '20', '40', '42.323', 'This is my first program!'.

print("int(20) = {}".format(int(20)))
print("int(40) = {}".format(int(40)))
print("int(42.323) = {}".format(int(42.323)))
print("int(This is my first program!) = {}".format(int('This is my first program!')))

Runing the previous code will generat the following result.

int(20) = 20
int(40) = 40
int(42.323) = 42
ValueError: invalid literal for int() with base 10: 'This is my first program!'

Example 2 Create a program that will take user input (integer only) and convert it to float, long, complex, str, repr, tuple, chr, unichr, hex and oct.

USER_INPUT = int(input("Enter an integer: "))
print("float(USER_INPUT) = {}".format(float(USER_INPUT)))
print("type(float(USER_INPUT)) = {}".format(type(float(USER_INPUT))))
print("complex(USER_INPUT) = {}".format(complex(USER_INPUT)))
print("type(complex(USER_INPUT)) = {}".format(type(complex(USER_INPUT))))
print("str(USER_INPUT) = {}".format(str(USER_INPUT)))
print("type(str(USER_INPUT)) = {}".format(type(str(USER_INPUT))))
print("repr(USER_INPUT) = {}".format(repr(USER_INPUT)))
print("type(repr(USER_INPUT)) = {}".format(type(repr(USER_INPUT))))
print("chr(USER_INPUT) = {}".format(chr(USER_INPUT)))
print("type(chr(USER_INPUT)) = {}".format(type(chr(USER_INPUT))))
print("hex(USER_INPUT) = {}".format(hex(USER_INPUT)))
print("type(hex(USER_INPUT)) = {}".format(type(hex(USER_INPUT))))
print("oct(USER_INPUT) = {}".format(oct(USER_INPUT)))
print("type(oct(USER_INPUT) = {}".format(type(oct(USER_INPUT))))
print("hex(USER_INPUT) = {}".format(hex(USER_INPUT)))
print("type(hex(USER_INPUT)) = {}".format(type(hex(USER_INPUT))))