Python | ldexp() function (original) (raw)

Last Updated : 14 Feb, 2023

ldexp() function is one of the Standard math library function in Python, which returns x * (2**i). This is also called as inverse of Python frexp() function.

Syntax: math.ldexp(x, i)

Parameters: x : Any valid number (+ve or -ve) i : Any valid number (+ve or -ve)

Returns : Returns the value of x * (2**i).

Time Complexity: O(1)

Auxiliary Space: O(1)

For example, if x = 3 and i = 4 then, Math.ldexp(3, 4) = 3*16 = 48.

Code #1:

Python3 `

Python3 code demonstrate ldexp() function

importing math library

import math

ldexp() Function on +ve nd -ve Numbers

print(math.ldexp(9, 3)) print(math.ldexp(-5, 2))

ldexp() Function on fractional Number

print(math.ldexp(3.5, 2)) print('%.2f' %math.ldexp(-6.8, 3))

`

Output:

72.0 -20.0 14.0 -54.40

Code #2:

Python3 `

Python3 code demonstrate ldexp() function

importing math library

import math

Tuple Declaration

tpl = (9, -5, 3.5, -6.8)

List Declaration

lst = [13, 4, 8.4, -6.7]

ldexp() Function on +ve nd -ve Numbers

print(math.ldexp(tpl[0], 3)) print(math.ldexp(tpl[3], 2))

ldexp() Function on fractional Number

print(math.ldexp(lst[1], 2)) print('%.2f' %math.ldexp(lst[2], 3))

`

Output:

72.0 -27.2 16.0 67.20

Code #3: If the X value or i value argument is not a number, ldexp() function will return TypeError.

Python3 `

Python3 code demonstrates when error occurs

importing the math library

import math

string value taken

print(math.ldexp('25', 5)) print(math.ldexp(25, '5'))

`

Output:

TypeError: a float is required TypeError: a float is required