degrees() and radians() in Python

The measurements of angles in mathematics are done using two units: degrees and radians. They are frequently used in math calculations involving angles and need conversion from one value to another. In Python, we can achieve these conversions using built-in functions from the math module.

degrees() Function

This function takes a radian value as parameter and returns the equivalent value in degrees. The return type is a float value.

Syntax

math.degrees(x)

Where x is the angle in radians.

Example

import math

# Converting radians to degrees
print("1 radian in degrees:", math.degrees(1))
print("0.5 radians in degrees:", math.degrees(0.5))
print("3.14159 radians in degrees:", math.degrees(3.14159))

1 radian in degrees: 57.29577951308232
0.5 radians in degrees: 28.64788975654116
3.14159 radians in degrees: 179.99942478929447

radians() Function

This function takes a degree value as parameter and returns the equivalent value in radians. The return type is a float value.

Syntax

math.radians(x)

Where x is the angle in degrees.

Example

import math

# Converting degrees to radians
print("1 degree in radians:", math.radians(1))
print("60 degrees in radians:", math.radians(60))
print("180 degrees in radians:", math.radians(180))

1 degree in radians: 0.017453292519943295
60 degrees in radians: 1.0471975511965976
180 degrees in radians: 3.141592653589793

Using NumPy for Angle Conversion

NumPy package also has built-in functions which can directly convert degrees to radians and vice versa. These functions are named deg2rad() and rad2deg().

Example

import numpy as np

# Converting using NumPy functions
print("90 degrees to radians:", np.deg2rad(90))
print("1.57 radians to degrees:", np.rad2deg(1.57))
print("Array conversion - degrees to radians:", np.deg2rad([0, 30, 45, 90]))

90 degrees to radians: 1.5707963267948966
1.57 radians to degrees: 89.95437383553924
Array conversion - degrees to radians: [0.         0.52359878 0.78539816 1.57079633]

Comparison

Conclusion

Use math.degrees() and math.radians() for single value conversions. For array operations or scientific computing, NumPy's deg2rad() and rad2deg() functions are more efficient and support vectorized operations.