How can I change all value with same function in numpy array?-CodePudding

Let's assume that there is sigmoid functions that I defined.

def sigmoid(self, x):
   return something

I have arrays.

a = np.array([1, 2, 3, 4, 5, 6])

I wanna make "a" like this:

a =  [sigmoid(1), sigmoid(2), sigmoid(3), sigmoid(4), sigmoid(5), sigmoid(6)]

Is there anyway that don't use for loops? I mean, some numpy functions?

CodePudding user response：

You can just call the function manually

a = np.array([sigmoid(1),sigmoid(2),..])

or using list-comprehension

a = np.array([sigmoid(i 1) for i in range(6)])

But theres not, as far as I know, a specific numpy function that does it as such

CodePudding user response：

If you want to do this with function you can use numpy.vectorize like below:

>>> def sigmoid(x):
...    return x   3

>>> a = np.array([1, 2, 3, 4, 5, 6])
>>> vfunc = np.vectorize(sigmoid)
>>> vfunc(a)
array([4, 5, 6, 7, 8, 9])

Or you can do this with lambda like below:

>>> sigmoid = lambda x: x   3
>>> sigmoid(a)
array([4, 5, 6, 7, 8, 9])