What exactly does numpy.exp() do?
PythonNumpyStatisticsExpPython Problem Overview
I'm very confused as to what np.exp() actually does. In the documentation it says that it: "Calculates the exponential of all elements in the input array." I'm confused as to what exactly this means. Could someone give me more information to what it actually does?
Python Solutions
Solution 1 - Python
The exponential function is e^x where e is a mathematical constant called Euler's number, approximately 2.718281. This value has a close mathematical relationship with pi and the slope of the curve e^x is equal to its value at every point. np.exp() calculates e^x for each value of x in your input array.
Solution 2 - Python
It calculates ex for each x in your list where e is Euler's number (approximately 2.718). In other words, np.exp(range(5)) is similar to [math.e**x for x in range(5)].
Solution 3 - Python
exp(x) = e^x where e= 2.718281(approx)
import numpy as np
ar=np.array([1,2,3])
ar=np.exp(ar)
print ar
outputs:
[ 2.71828183 7.3890561 20.08553692]